taxonID	type	description	language	source
103A87D9FC57FFE9FF19F880FB56FE6C.taxon	description	The type species of the subgenus Psomophus is the Nearctic Euconnus callidus Casey, 1897. Its body form and even the structure of the aedeagus (illustrated in Jałoszyński (2017 c )) are highly similar to those of the Japanese E. debilis (Sharp, 1874), redescribed by Jałoszyński (2022). Both species share clearly trimerous antennal clubs, round heads with bristles on tempora, subconical pronota narrowing anterad and bearing thick bristles on sides, protibiae in males with apices strongly bent mesad, and aedeagi with clearly delimited distal regions and an oval sclerotized median endophallic structure. Although some other species currently placed in Psomophus also show a similar set of features, only two more Eastern Palaearctic species so closely resemble E. callidus: E. chinensis Franz, 1985 a [China: Fujian], and E. nuperus Kurbatov, 2006 [Russian Far East: Amurskaya Oblast]. As E. debilis was recently redescribed in detail (Jałoszyński 2022), and E. nuperus was adequately described and can be identified using Kurbatov’s (2006) accurate illustrations, only E. chinensis is redescribed below. A new species belonging in this group is here described as E. multiinsularis sp. n. The above-listed set of morphological characters (except for the oval or ring-like sclerotized endophallic structure, which does not occur in some species) can be used to define a ‘ true Psomophus ’. However, similar species are known, and also have been placed in Psomophus (see Discussion) that show a remarkably different form of the aedeagus or / and unmodified male protibiae. Such species are not included in the E. callidus group.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC54FFE8FF19FDB4FBD2FED8.taxon	materials_examined	Type material studied. Holotype (China: Fujian): ♂, three labels: “ Shaowu, 500 m / Fukien, China / 17.11.1946 ” [white, printed and handwritten], “ Euconnus / (Spanioconnus) / chinensis m. / det. H. Franz ” [white, handwritten and printed], “ Holotypus ” [red, handwritten] (NHMW). Paratypes (3 exx): 2 ♀♀ and 1 ex. of unknown sex, same locality label as for holotype, lacking any other labels (but matching data given in original description for paratypes) (NHMW).	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC54FFE8FF19FDB4FBD2FED8.taxon	diagnosis	Diagnosis. Antennal club clearly trimerous and slender; head round; pronotum subconical and broadest near base but only moderately narrowing anterad, with one pair of antebasal pits connected by distinct transverse groove and with distinct sublateral carinae; protibiae in males strongly bent mesad in apical regions; aedeagus not strongly sclerotized, in ventral view with distinct ring-like sclerotized endophallic structure and conspicuously long dorsal apical plate, with sub-parallel sides in proximal half, rounded in distal region and forming angulate, broadly subtriangular apex.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC54FFE8FF19FDB4FBD2FED8.taxon	description	Description. Body of male (Fig. 1) elongate, moderately convex; pigmentation moderately dark umbra brown, with legs, antennomeres except 9 ‒ 11 and palps distinctly lighter, antennal clubs slightly infuscate; body covered with setae distinctly lighter than cuticle; BL 1.10 mm. Head (Fig. 1) broadest at eyes, indistinctly transverse, HL 0.20 mm, HW 0.23 mm; tempora in dorsal view about as long as eyes, behind eyes strongly and evenly convergent posterad, posterior margin of vertex weakly arcuate, not bulging posterodorsad. Frons and vertex with unremarkable, fine punctures, glossy; setae sparse and suberect, tempora with sparse thick bristles. Antennae slender, with loosely assembled and slender trimerous club, AnL 0.50 mm, scape and pedicel each elongate, antennomeres 3 – 5 each indistinctly longer than wide, 6 – 8 each as long as broad, 9 – 11 enlarged, 9 and 10 each as long as broad, 11 distinctly shorter than 9 and 10 combined, about 1.6 × as long as broad. Pronotum subconical and broadest shortly in front of base, moderately narrowing anterad; PL 0.28 mm, PW 0.28 mm. Sides weakly rounded, base with one pair of small but distinct pits connected by transverse groove, and with distinct, sharply marked sublateral carinae. Punctures and setae on disc similar to those on frons and vertex; sides of pronotum with moderately dense thick bristles. Elytra together oval, broadest distinctly in front of middle; EL 0.63 mm, EW 0.48 mm, EI 1.32; humeral calli distinct and slightly elongate, mesally demarcated by elongate impressions; elytral apices separately rounded. Punctures fine, superficial and inconspicuous; setae sparse but distinctly longer than those on pronotal disc, suberect. Legs slender, protibiae modified, with apical regions strongly bent mesad. Aedeagus (Figs 2 – 5) weakly elongate, AeL 0.20 mm; median lobe in ventral view broadest in distal half, in lateral view strongly curved, dorsal apical plate in ventral view elongate, with sides nearly parallel in proximal half, rounded and converging distad to form subtriangular apex; endophallus with ring-like sclerotized structure. Parameres slender but short, not reaching apex of median lobe, each with two long apical setae. Female. Similar to male but with straight, unmodified distal region of protibia. BL 1.16 mm; HL 0.24 mm, HW 0.25 mm, AnL 0.48 mm; PL 0.28 mm, PW 0.30 mm; EL 0.65 mm, EW 0.50 mm, EI 1.30.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC54FFE8FF19FDB4FBD2FED8.taxon	distribution	Distribution. Known only from the type locality in Fujian, China.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC54FFE8FF19FDB4FBD2FED8.taxon	discussion	Remarks. This species is externally extremely similar to the Japanese E. debilis and the Far Russian E. nuperus; females of these species can be identified only by association with males collected in the same spot. Aedeagi within this group are also similar, but differ clearly in the apical structures, especially in the shape of the dorsal apical plate (illustrated for E. debilis in Jałoszyński (2022), and for E. nuperus in Kurbatov (2006 )).	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC55FFEDFF19F98DFEB2FB5C.taxon	description	(Figs 6 – 18, 109)	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC55FFEDFF19F98DFEB2FB5C.taxon	materials_examined	Type material studied. Holotype (Japan: Kagoshima Prefecture: Takarajima Is.): ♂, three labels: “ Arakizaki / Takarajima Is. / Tokara, Ryukyu ” [white, printed], “ 22. iii. 1992 / S. Nomura leg. ” [white, printed], “ EUCONNUS s. str. / multiinsularis m. / P. Jałoszyński, ’ 22 / HOLOTYPUS ” [red, printed] (NSMT). Paratypes (9 exx): Takarajima Is.: ♂, same data as for holotype; Tokunoshima Is.: 2 ♂♂, “ Yonama / Tokunoshima Is. / Kagoshima Pref. ” [white, printed], “ 4. v. 1988 / S. Nomura leg. ” [white, printed]; Okinawa-jima Is.: 1 ♂, 1 ♀, “ [Okinawa: RYUKYU] / Mt. Nishimedake / 360 m, Kunigami / 19. X. 1987 / M. Sakai leg. ” [white, printed], “ Leaf litter ” [white with black frame, printed]; 1 ♂, “ Yona, kunigami / Okinawa Pref. ” [white, printed], “ 15. iii. 1985 / S. Nomura leg. ” [white, printed]; 2 ♀♀, “ (RYUKYUS) / Mt. Yonahadake / Okinawa Island / 6. X. 1978 / K. Ishikawa ” [white, printed], ” collected from / soil by using / Berlese funnel ” [white, printed]; Amami Ôshima Is.: ♂, “ JAPAN, KAGOSHIMA Pref. / Amami Ôshima, Yui-dake / 25 - 28 - 2004, white pan trap / Toshiharu Mita leg. ” [white, printed]. Paratypes in NSMT, EUMJ and cPJ, all with yellow “ PARATYPUS ” labels similar to that with holotype.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC55FFEDFF19F98DFEB2FB5C.taxon	diagnosis	Diagnosis. Antennal club clearly trimerous and slender; head round; pronotum subconical and broadest near base but only moderately narrowing anterad, with one pair of antebasal pits connected by distinct transverse groove and with distinct sublateral carinae; protibiae in males strongly bent mesad in apical regions; aedeagus conspicuously strongly, darkly sclerotized and strongly elongate, endophallic sclerites not fused into ring-like structure, with bulbous portion nearly parallel-sided or broadest in distal third and with relatively small dorsal apical plate, which in ventral view is only slightly elongate, in proximal half weakly narrowing distad, and in distal half abruptly narrowing to form subtrapezoidal and truncate apex.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC55FFEDFF19F98DFEB2FB5C.taxon	description	Description. Body of male (Fig. 6) elongate, moderately convex; pigmentation moderately dark umbra brown, legs and palps distinctly lighter, antennal clubs not infuscate; body covered with setae distinctly lighter than cuticle; BL 1.28 – 1.40 mm. Head broadest at eyes, indistinctly transverse, HL 0.28 mm, HW 0.28 – 0.30 mm; tempora in dorsal view about 1.5 × as long as eyes, behind eyes strongly and evenly convergent posterad, posterior margin of vertex weakly arcuate, not bulging posterodorsad. Frons and vertex with unremarkable, fine punctures, glossy; setae sparse and suberect, tempora with sparse thick bristles. Antennae slender, with loosely assembled and slender trimerous club, AnL 0.58 – 0.63 mm, scape and pedicel each elongate, antennomeres 3 – 8 each indistinctly longer than wide, 9 – 11 enlarged, 9 and 10 each indistinctly transverse, 11 distinctly shorter than 9 and 10 combined, about 1.5 × as long as broad. Pronotum subconical and broadest shortly in front of base, moderately narrowing anterad; PL 0.30 – 0.34 mm, PW 0.33 – 0.35 mm. Sides weakly rounded, base with one pair of small but distinct pits connected by transverse groove, and with distinct, sharply marked sublateral carinae. Punctures and setae on disc similar to those on frons and vertex; sides of pronotum with moderately dense thick bristles. Elytra together oval, broadest distinctly in front of middle; EL 0.70 – 0.80 mm, EW 0.53 – 0.55 mm, EI 1.33 – 1.45; humeral calli distinct and slightly elongate, mesally demarcated by elongate impressions; elytral apices separately rounded. Punctures distinct but shallow, those near median area of both elytra separated by spaces slightly wider than diameters of punctures; setae sparse but much longer than those on pronotal disc, suberect. Legs slender, protibiae modified, with apical regions strongly bent mesad. Aedeagus (Figs 7 – 18) strongly elongate and strongly sclerotized, AeL 0.33 mm; median lobe in ventral view broadest in distal third or nearly parallel-sided, in lateral view strongly curved, dorsal apical plate in ventral view elongate, with sides weakly converging distad in proximal half, rapidly narrowed in distal region to form subtrapezoidal and truncate apex; endophallus lacking ring-like sclerotized structure, poorly demarcated and situated in apical region. Parameres slender but short, not reaching apex of median lobe, each with two long apical setae. Some variability in the shape of median lobe was found among specimens collected on various islands (Figs 7 – 18), but differences are minor and seem to represent only interspecific variation. Female. Similar to male but with straight, unmodified distal region of protibiae. BL 1.28 – 1.34 mm; HL 0.28 mm, HW 0.30 mm, AnL 0.58 – 0.60 mm; PL 0.30 – 0.31 mm, PW 0.33 – 0.35 mm; EL 0.70 – 0.75 mm, EW 0.55 – 0.60 mm, EI 1.25 – 1.27.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC55FFEDFF19F98DFEB2FB5C.taxon	distribution	Distribution. Islands of northern and central Ryūkyū: Takarajima, Tokunoshima, Amami Ôshima, and Okinawajima (Fig. 109).	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC55FFEDFF19F98DFEB2FB5C.taxon	etymology	Etymology. The adjective multiinsularis refers to a distribution on several islands.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC55FFEDFF19F98DFEB2FB5C.taxon	discussion	Remarks. Although this species externally resembles closely E. nuperus, E. debilis and E. chinensis, it can be easily identified by its unique, unusually elongate and slender aedeagus. Aedeagi of specimens collected on different islands were studied (Figs 11 – 18) and only small differences were found, attributable to intraspecific variability. No external characters differ among populations inhabiting different islands. Females can be distinguished from the three similar congeners by slightly longer and slenderer body. Interestingly, the northern Euconnus debilis and the southern E. multiinsularis co-occur on the small island of Takarajima, which represents the southernmost known locality for the former, and the northernmost for the latter (Fig. 109).	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC50FFEDFF19FA98FD92F9B4.taxon	description	One new Japanese species described below as E. rectitibia is externally similar to E. debilis and allied species, but males do not have any protibial modifications, and its aedeagus is of a clearly different form, in ventral view drop-shaped, with median elongate and darkly sclerotized endophallic structure situated near middle of the bulbous portion of the median lobe. Moreover, the antennae, including also trimerous clubs, are much slenderer than those in the Euconnus callidus species group. Because of close external similarity to species of the Euconnus callidus group, this interesting taxon is treated here.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC50FFE2FF19F9F1FBA3FDF8.taxon	description	(Figs 19 – 23, 24 – 28, 110)	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC50FFE2FF19F9F1FBA3FDF8.taxon	materials_examined	Type material studied. Holotype (Japan: Saitama Prefecture): ♂, two labels: “ Shinjuku-shinden (Edogawa riverbank) / Shōwa-machi, Saitama Pref. / [Honshu, JAPAN] / 16. xii. 2004, S. Nomura lg. ” [white, printed], “ EUCONNUS s. str. / rectitibia m. / P. Jałoszyński, ’ 22 / HOLOTYPUS ” [red, printed] (NSMT). Paratypes (3 exx): Saitama Pref.: ♀, same data as for holotype; Niigata Pref.: ♂, “ Kuramitsu / Shibata C. / Niigata Pref. ” [white, printed], “ 3. vii. 1998 / Hiroshi Koike ” [white, printed]; Fukuoka Pref.: ♂, “ [Kyushu, JAPAN] / 12. vii. 1997 / Kenshi Otsuka leg. ” [white, printed], Chikugogawa riv. / Tanushimaru-machi / Fukuoka Pref. ” [white, printed]. Paratypes with yellow “ PARATYPUS ” labels similar to that with holotype, deposited in NSMT and cPJ.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC50FFE2FF19F9F1FBA3FDF8.taxon	diagnosis	Diagnosis. Antennal club clearly trimerous and slender; head round; pronotum nearly parallel-sided in posterior half and with rounded sides in anterior third converging anterad, with one pair of antebasal pits and transverse groove reduced to slightly transverse median antebasal pit, and with distinct sublateral carinae; protibiae in males unmodified, straight; aedeagus moderately sclerotized, in ventral view drop-shaped, with subtrapezoidal dorsal apical plate and with simple endophallus with darkly sclerotized submedian elongate structure.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC50FFE2FF19F9F1FBA3FDF8.taxon	description	Description. Body of male (Figs 19, 24) elongate, moderately convex; pigmentation moderately dark umbra brown, legs and palps indistinctly lighter, antennal clubs barely discernibly darkened; body covered with setae distinctly lighter than cuticle; BL 1.15 – 1.23 mm. Head broadest at eyes, indistinctly transverse, HL 0.23 mm, HW 0.25 mm; tempora in dorsal view about twice as long as eyes, behind eyes strongly and evenly convergent posterad, posterior margin of vertex weakly arcuate, not bulging posterodorsad. Frons and vertex with unremarkable, fine punctures, glossy; setae sparse and suberect, tempora with sparse thick bristles. Antennae slender, with loosely assembled and slender trimerous clubs, AnL 0.65 – 0.68 mm, all antennomeres elongate, 11 distinctly shorter than 9 and 10 combined, about twice as long as broad. Pronotum equally broad between base and anterior third; PL 0.25 – 0.30 mm, PW 0.28 – 0.30 mm. Sides posteriorly nearly straight, in anterior third rounded and converging anterad, base with one pair of small but distinct pits, transverse groove reduced to slightly transverse median antebasal pit, sublateral carinae sharply marked and distinct. Punctures and setae on disc similar to those on frons and vertex; sides of pronotum with dense thick bristles, sparse bristles are also present on disc. Elytra together oval, broadest slightly in front of middle; EL 0.65 – 0.70 mm, EW 0.50 – 0.53 mm, EI 1.29 – 1.40; humeral calli distinct and slightly elongate, mesally demarcated by elongate impressions; elytral apices separately rounded. Punctures distinct but very shallow, superficial and diffuse, unremarkable; setae sparse but much longer than those on pronotal disc, suberect. Legs slender, protibiae unmodified, straight. Aedeagus (Figs 20 – 23, 25 – 28) stout, drop-shaped, moderately strongly sclerotized, AeL 0.20 mm; median lobe in ventral view broadest near middle or in submedian proximal region, sides rounded, in lateral view median lobe distinctly curved, dorsal apical plate in ventral view elongate, subtrapezoidal, with median subtriangular projection on apical margin; endophallus lacking ring-like sclerotized structure, with tubular (flagellar?) component in subapical region (clearly visible in lateral view) and submedian elongate sclerotized structure. Parameres slender but short, not reaching apex of median lobe, each with two long apical setae. Variability in aedeagal structures is discussed in Remarks. Female. Externally indistinguishable from male. BL 1.18 mm; HL 0.23 mm, HW 0.24 mm, AnL 0.65 mm; PL 0.28 mm, PW 0.28 mm; EL 0.68 mm, EW 0.50 mm, EI 1.35.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC50FFE2FF19F9F1FBA3FDF8.taxon	distribution	Distribution. Japan: Kyūshū and central Honshū (regions Kantō and Chūbu) (Fig. 110).	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC50FFE2FF19F9F1FBA3FDF8.taxon	etymology	Etymology. The epithet rectitibia (noun in apposition) refers to the unmodified, straight (Latin rectus) protibiae in males.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC50FFE2FF19F9F1FBA3FDF8.taxon	discussion	Remarks. Specimens from Saitama Pref. (Figs 19 – 23) differ from those from Niigata and Fukuoka Prefectures in small details of the aedeagus. However, the illustrated aedeagi (compare Figs 23 and 26) seem to be in a slightly different condition — the one in Figs 20 – 23 is in an early stage of eversion, with swollen membranous ventral subapical region (which makes the dorsal apical plate appear shorter), and the tubular subapical endophallic structure almost perpendicular in relation to the long axis of the aedeagus, while in Figs 25 – 28 this tubular (flagellar?) element is oriented approximately on the coronal plane of the aedeagus. Consequently, in ventral view, this tubular structure in Figs 25, 27 is visible as an elongate subtriangular subapical component situated in the proximal half of the dorsal apical plate, whereas in Figs 20, 22 it is almost horizontal and visible as if it was a cross-section – a sclerotized cordiform spot in the same region. According to Shûhei Nomura, the holotype and one paratype of this species were collected on a floodbank of the Edogawa River, from decaying plant debris accumulated on a concrete embankment. The type locality spelled “ Shinjuku-shinden ” (not to be confused with Shinjuku in Tokyo) on the label of the holotype can also be read “ Shinshuku-shinden ” (Shûhei Nomura, in email to the author dated 25.05.2022).	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC5FFFE2FF19FD3CFB63FC74.taxon	description	This group of three Japanese species is characterized by compact antennae with antennomeres 3 ‒ 10 distinctly transverse and with compact trimerous antennal clubs; aedeagi with rapidly narrowed apical regions and paired submedian endophallic sclerites, symmetrical in two species and asymmetrical in one; parameres with numerous apical setae. In two species males have conspicuous cephalic modifications (a transverse frontal groove and lateral impressions), in one species, the modification is barely marked, but can also be seen as a faint transverse frontal impression. All species share also distinctly elongate heads with the vertex bulging posterodorsad, in contrast to species that belong in the E. callidus group which have rounded heads with non-bulging vertexes.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC5FFFE0FF19FBB1FEEEFD1C.taxon	description	(Figs 29 – 36, 110)	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC5FFFE0FF19FBB1FEEEFD1C.taxon	materials_examined	Type material studied. Holotype (Japan: Kanagawa Prefecture): ♂, three labels: “ JAPAN, Kanagawa Pref. / Sagamiko / 25 V 2002 / leg. P. JAŁOSZYŃSKI ” [white, printed], “ rotten wood / under dead dec. tree ” [white, printed], “ EUCONNUS s. str. / kirin m. / P. Jałoszyński, ’ 22 / HOLOTYPUS ” [red, printed] (NSMT). Paratype: ♀, “ JAPAN, Kanagawa Pref. / Sagamiko / 14 VII 2002 / leg. P. JAŁOSZYŃSKI ” [white, printed]. Paratype with yellow “ PARATYPUS ” label similar to that with holotype, deposited in cPJ.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC5FFFE0FF19FBB1FEEEFD1C.taxon	diagnosis	Diagnosis. Antennal club clearly trimerous and stout; head distinctly elongate, with vertex bulging posterodorsad and in males with pair of large and clearly delimited lateral frontal impressions connected at middle by deep transverse groove; pronotum subconical, with one pair of tiny antebasal pits connected by extremely faint, barely noticeable transverse groove, and with indistinct sublateral carinae; protibiae in males unmodified, weakly and evenly curved; aedeagus weakly sclerotized, in ventral view drop-shaped, with symmetrical pair of strongly elongate endophallic sclerites in subapical region resembling horns with several short and pointed branches.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC5FFFE0FF19FBB1FEEEFD1C.taxon	description	Description. Body of male (Fig. 29) elongate, strongly convex; pigmentation moderately dark brown, legs, antennae and palps indistinctly lighter, antennal clubs not darkened; body covered with setae distinctly lighter than cuticle; BL 1.23 mm. Head (Figs 35 ‒ 36) nearly as large as pronotum, broadest at eyes, distinctly elongate, HL 0.30 mm, HW 0.25 mm; tempora in dorsal view over twice as long as eyes, behind eyes strongly and evenly convergent posterad, posterior margin of vertex strongly rounded, strongly bulging posterodorsad. Frons with deep transverse groove broadened at each side, median region directly behind groove slightly impressed, and region in front of groove distinctly bulging (best visible in lateral view; Fig. 35); each side of anterior head region with large, oval impression. Frons and vertex with unremarkable, fine punctures, glossy; setae sparse and suberect, frontal groove surrounded by denser and shorter nearly recumbent setae, tempora with dense but short thick bristles. Antennae short and compact, with compact and broad trimerous club, AnL 0.43 mm, scape and pedicel each elongate, antennomeres 3 ‒ 10 each transverse (3 ‒ 8 weakly, 9 and 10 strongly so), 11 slightly shorter than 9 and 10 combined, about as long as broad. Pronotum subconical, broadest slightly behind middle; PL 0.30 mm, PW 0.28 mm. Base with one pair of tiny antebasal pits connected by extremely faint, barely noticeable transverse groove, and with indistinct sublateral carinae. Punctures and setae on disc similar to those on frons and vertex; sides of pronotum with sparse thick bristles. Elytra together oval, broadest slightly in front of middle; EL 0.63 mm, EW 0.43 mm, EI 1.47; humeral calli poorly marked and mesally not demarcated by elongate impressions; elytral apices separately rounded. Punctures distinct but very shallow, superficial and diffuse, unremarkable; setae sparse and only slightly longer than those on pronotal disc, only slightly suberect. Legs slender, protibiae unmodified, weakly and evenly curved. Aedeagus (Figs 30 – 34) stout, drop-shaped, weakly sclerotized, AeL 0.23 mm; median lobe in ventral view broadest in subapical region, sides rounded, in lateral view median lobe weakly curved, dorsal apical plate in ventral view subtriangular but with narrowly truncate apex; endophallus in subapical region with conspicuous pair of elongate and barbed, horn-like sclerites (Fig. 33). Parameres broad and short, not reaching apex of median lobe, each with 4 – 5 apical and subapical setae of various lengths, parameral base with a thick collar. Female. Externally similar to male (including conspicuously large head), but lacking modifications on frons. BL 1.25 mm; HL 0.30 mm, HW 0.25 mm, AnL 0.40 mm; PL 0.30 mm, PW 0.30 mm; EL 0.65 mm, EW 0.48 mm, EI 1.37.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC5FFFE0FF19FBB1FEEEFD1C.taxon	distribution	Distribution. Japan: Honshū (Kantō region) (Fig. 110).	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC5FFFE0FF19FBB1FEEEFD1C.taxon	etymology	Etymology. The epithet kirin (noun in apposition) refers to a pair of endophallic sclerites (Fig. 33) that resemble horns on the head of the kirin, a mythical creature well-known in Japan.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC5FFFE0FF19FBB1FEEEFD1C.taxon	discussion	Remarks. The only nominal species similar to E. kirin is E. yaimanus (see next description), whose male also has a strongly modified head. The latter species, however, occurs on the south-westernmost Yaeyama Islands, has clearly different modifications of the frons (Figs 35 ‒ 36 vs. 46 ‒ 47), and different aedeagal structures (Figs 30 ‒ 34 vs. 38 ‒ 45). The holotype and paratype of this species were collected by sifting leaf litter and rotten wood on the western slope of Mt. Arashiyama near the lake Sagamiko (municipality Sagamihara), at the altitude ~ 350 m, in a deciduous forest with oaks.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC5DFFE5FF19FA6FFA2DFE48.taxon	description	(Figs 37 – 47, 110)	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC5DFFE5FF19FA6FFA2DFE48.taxon	materials_examined	Type material studied. Holotype (Japan: Okinawa Prefecture: Iriomote-jima Is.): ♂, two labels: “ JAPAN, OKINAWA Pref. / Kanpiree, St. 1 (80 m) / Iriomote-jima / 20. iii. 2004 / leg. S. Nomura ” [white, printed], “ EUCONNUS s. str. / yaimanus m. / P. Jałoszyński, ’ 22 / HOLOTYPUS ” [red, printed] (NSMT). Paratype: Yonaguni-jima Is.: ♂, “ JAPAN, Okinawa Pref. / Yonaguni-jima, Mt. Kubura- / dake, FIT, 9 - 12. ix. 2004 / Koji & Shiho Arai leg. ” [white, printed]. Paratype with yellow “ PARATYPUS ” label similar to that with holotype, deposited in cPJ.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC5DFFE5FF19FA6FFA2DFE48.taxon	diagnosis	Diagnosis. Antennal club clearly trimerous and stout; head distinctly elongate, with vertex bulging posterodorsad and in males with pair of small and diffuse lateral frontal impressions connected at middle by deep transverse groove; pronotum subconical, with one pair of tiny antebasal pits connected by extremely faint, barely noticeable transverse impression, and with indistinct sublateral carinae; protibiae in males unmodified, weakly and evenly curved; aedeagus weakly sclerotized, in ventral view bottle-shaped, with asymmetrical group of strongly elongate endophallic sclerites in subapical region, longest sclerite (in ventral view on the right side) strongly curved distomesad.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC5DFFE5FF19FA6FFA2DFE48.taxon	description	Description. Body of male (Fig. 37) elongate, strongly convex; pigmentation moderately dark brown, only tarsi, palps and antennal clubs indistinctly lighter; body covered with setae distinctly lighter than cuticle; BL 1.08 – 1.09 mm. Head (Figs 46 ‒ 47) smaller (especially narrower) than pronotum, broadest at eyes, distinctly elongate, HL 0.25 mm, HW 0.20 – 0.21 mm; tempora in dorsal view over twice as long as eyes, behind eyes strongly and evenly convergent posterad, posterior margin of vertex strongly rounded, strongly bulging posterodorsad. Frons with deep transverse groove broadened at each side, median region directly behind groove convex, and region in front of groove distinctly bulging (best visible in lateral view; Fig. 47); each side of anterior head region with small, transverse impression. Frons and vertex with unremarkable, fine punctures, glossy; setae sparse and suberect, frontal groove posteriorly bordered by transverse row of dense and short nearly recumbent setae, tempora with dense but short thick bristles. Antennae short and compact, with compact and broad trimerous club, AnL 0.40 mm, scape and pedicel each elongate, antennomeres 3 ‒ 10 each transverse (3 ‒ 8 weakly, 9 and 10 strongly so), 11 slightly shorter than 9 and 10 combined, about as long as broad. Pronotum subconical, broadest slightly behind middle; PL 0.25 – 0.29 mm, PW 0.25 – 0.28 mm. Base with one pair of tiny antebasal pits connected by extremely faint, barely noticeable transverse impression, and with indistinct sublateral carinae. Punctures and setae on disc similar to those on frons and vertex; sides of pronotum with sparse thick bristles. Elytra together oval, broadest slightly in front of middle; EL 0.55 – 0.58 mm, EW 0.40 mm, EI 1.38 – 1.44; humeral calli poorly marked and mesally not demarcated by impressions; elytral apices separately rounded. Punctures distinct but very shallow, superficial and diffuse, unremarkable; setae sparse and only slightly longer than those on pronotal disc, only slightly suberect. Legs slender, protibiae unmodified, weakly and evenly curved. Aedeagus (Figs 38 – 45) stout, bottle-shaped, weakly sclerotized, AeL 0.20 mm; median lobe in ventral view almost equally broad from sub-basal third to subapical region, so that sides at middle are parallel, in lateral view median lobe weakly curved, dorsal apical plate in ventral view subtrapezoidal with (Figs 38, 40) or without (Figs 42, 44) additional median truncate projection; endophallus in subapical region with conspicuous asymmetrical group of elongate sclerites, of which the longest is strongly curved distomesad. Parameres broad and short, not reaching apex of median lobe, each with 4 – 5 apical and subapical setae of various lengths, parameral base with small collar. Female. Unknown.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC5DFFE5FF19FA6FFA2DFE48.taxon	distribution	Distribution. Japan, southern Ryūkyū: Iriomote-jima and Yonaguni-jima islands of the Yaeyama Archipelago (Fig. 110).	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC5DFFE5FF19FA6FFA2DFE48.taxon	etymology	Etymology. The epithet yaimanus is an adjective derived from the word Yaima, the name of Yaeyama Islands in the Yaimamuni, i. e., the Yaeyama language.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC5DFFE5FF19FA6FFA2DFE48.taxon	discussion	Remarks. This species is most similar to E. kirin; see Remarks for the latter. Males from two islands (Iriomote and Yonaguni) do not differ in external characters, although minor differences in the apical region of the aedeagus were found, and even smaller differences in the endophallic sclerites (Figs 38 – 41 vs. 42 – 45). I treat these specimens as conspecific, but a larger sample is required to verify this assumption.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC58FFE5FF19FDADFAB3F844.taxon	description	(Figs 48 – 53, 110)	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC58FFE5FF19FDADFAB3F844.taxon	materials_examined	Type material studied. Holotype (Japan: Okinawa Prefecture: Okinawa-jima Is.): ♂, two labels: “ JAPAN, OKINAWA Island / Oura Bay, Futami - Wansaka / Oura Park, 20 - 140 m, roadside / 10.02.2019 / leg. P. JAŁOSZYŃSKI ” [white, printed], “ EUCONNUS s. str. / uchinaanchu m. / P. Jałoszyński, ’ 22 / HOLOTYPUS ” [red, printed] (NSMT).	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC58FFE5FF19FDADFAB3F844.taxon	diagnosis	Diagnosis. Antennal club clearly trimerous and stout; head distinctly elongate, with vertex bulging posterodorsad and in males with faint, barely discernible transverse groove between supraantennal tubercles, lacking lateral impressions; pronotum nearly round, with one pair of tiny antebasal pits connected by extremely faint, barely noticeable transverse impression, and with indistinct sublateral carinae; protibiae in males unmodified, weakly and evenly curved; aedeagus weakly sclerotized, in ventral view bottle-shaped, with symmetrical pair of strongly elongate and distomesally curved endophallic sclerites in subapical region.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC58FFE5FF19FDADFAB3F844.taxon	description	Description. Body of male (Fig. 48) elongate, strongly convex; pigmentation moderately light brown, appendages not distinctly lighter; body covered with setae distinctly lighter than cuticle; BL 1.20 mm. Head smaller (especially narrower) than pronotum, broadest at eyes, distinctly elongate, HL 0.30 mm, HW 0.24 mm; tempora in dorsal view over twice as long as eyes, behind eyes strongly and evenly convergent posterad, posterior margin of vertex strongly rounded, strongly bulging posterodorsad. Frons with indistinct transverse groove between supraantennal tubercles, lacking lateral impressions. Frons and vertex with unremarkable, fine punctures, glossy; setae sparse and suberect, tempora with dense but short thick bristles. Antennae short and compact, with compact and broad trimerous club, AnL 0.40 mm, scape and pedicel each elongate, antennomeres 3 ‒ 10 each transverse (3 ‒ 8 weakly, 9 and 10 strongly so), 11 slightly shorter than 9 and 10 combined, about as long as broad. Pronotum almost round, broadest indistinctly behind middle; PL 0.30 mm, PW 0.28 mm. Base with one pair of tiny antebasal pits connected by faint transverse impression, and with indistinct sublateral carinae. Punctures and setae on disc similar to those on frons and vertex; sides of pronotum with dense thick bristles. Elytra together oval, broadest slightly in front of middle; EL 0.60 mm, EW 0.43 mm, EI 1.41; humeral calli small but clearly marked and mesally demarcated by short elongate impressions; elytral apices separately rounded. Punctures distinct but very shallow, superficial and diffuse, unremarkable; setae sparse and only slightly longer than those on pronotal disc, only slightly suberect. Legs slender, protibiae unmodified, weakly and evenly curved. Aedeagus (Figs 49 – 53) moderately elongate, bottle-shaped, weakly sclerotized, AeL 0.25 mm; median lobe in ventral view broadest in subapical region, in lateral view median lobe weakly curved, dorsal apical plate in ventral view elongate subtrapezoidal with truncate median portion; endophallus in subapical region with conspicuous symmetrical pair of elongate sclerites strongly curved distomesad (Fig. 52). Parameres broad and short, not reaching apex of median lobe, each with 5 apical and subapical setae of various lengths, parameral base with small collar. Female. Unknown.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC58FFE5FF19FDADFAB3F844.taxon	distribution	Distribution. Japan, central Ryūkyū: Okinawa-jima Is. (Fig. 110).	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC58FFE5FF19FDADFAB3F844.taxon	etymology	Etymology. The epithet uchinaanchu (noun in apposition) is borrowed from Uchinaaguchi, the language of Okinawa, and means an inhabitant of Okinawa-jima.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC58FFE5FF19FDADFAB3F844.taxon	discussion	Remarks. This species is unique in having a pair of elongate, curved endophallic sclerites and the head in males indistinctly modified, with only a trace of shallow transverse groove between supraantennal tubercles.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC59FFFBFF19F934FC98FE34.taxon	description	This group of two Japanese species described below (several more are known to me from females only) is characterized by a tiny (around 1 mm) and slender body form, round head, subconical pronota, indistinctly tetramerous (pseudotetramerous or pseudotrimerous, depending on interpretation), loosely assembled antennal clubs, and the aedeagi that resemble copulatory organs of the European species previously placed in the subgenus Napochus Thomson, i. e. drop-shaped, with distinct ventral and dorsal apical plates, of which the dorsal one is longer, and with symmetrical endophalli and paired small subapical projections situated near distal region of the ventral apical plate.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC46FFFBFF19FE71FDC9F844.taxon	description	(Figs 54 – 58, 111)	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC46FFFBFF19FE71FDC9F844.taxon	materials_examined	Type material studied. Holotype (Japan: Kanagawa Prefecture): ♂, two labels: “ JAPAN, Kanagawa Pref. / Sagamiko env., ca. 300 m / 19 IV 2003 / leg. P. Jałoszyński ” [white, printed], “ EUCONNUS s. str. / pseudotrimerus m. / P. Jałoszyński, ’ 22 / HOLOTYPUS ” [red, printed] (NSMT).	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC46FFFBFF19FE71FDC9F844.taxon	diagnosis	Diagnosis. Antennal club with antennomere 8 larger than 7 but much smaller than 9; head round, with vertex not bulging posterodorsad; pronotum subconical and broadest at base, with one pair of distinct antebasal pits connected by also distinct transverse groove, and with pair of distinct sublateral carinae; head and protibiae in males unmodified; aedeagus weakly sclerotized, in ventral view with broadly rounded apical margin of dorsal apical plate, which in lateral view is strongly bent dorsad; ventral apical plate narrower than dorsal one and also broadly rounded at apex, between plates pair of distally divergent sublateral projections can be seen.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC46FFFBFF19FE71FDC9F844.taxon	description	Description. Body of male (Fig. 54) elongate, flattened; pigmentation moderately light brown, appendages distinctly lighter; body covered with setae distinctly lighter than cuticle; BL 0.93 mm. Head smaller than pronotum, broadest at eyes, round, HL 0.18 mm, HW 0.18 mm; tempora in dorsal view about as long as eyes, behind eyes strongly and evenly convergent posterad, posterior margin of vertex strongly rounded, not bulging posterodorsad. Frons and vertex with unremarkable, fine punctures, glossy; setae sparse and suberect, tempora and posterior margin of vertex with dense thick bristles. Antennae short and compact, but with loosely assembled club, AnL 0.38 mm, scape and pedicel each elongate, antennomeres 3 ‒ 6 each transverse, 7 as long as broad, 8 ‒ 10 gradually broadening, 8 slightly transverse, 9 and 10 each strongly transverse, 11 slightly shorter than 9 and 10 combined, about as long as broad. Pronotum subconical, broadest at base; PL 0.23 mm, PW 0.23 mm. Base with one pair of distinct antebasal pits connected by distinct transverse impression, and with distinct sublateral carinae. Punctures and setae on disc similar to those on frons and vertex; sides of pronotum with dense thick bristles. Elytra together oval, broadest clearly in front of middle; EL 0.53 mm, EW 0.35 mm, EI 1.50; humeral calli small but clearly marked and each mesally demarcated by round basal elytral impression; elytral apices separately rounded. Punctures indistinct, superficial and unremarkable; setae sparse and not longer than those on pronotal disc, but slightly thicker, suberect. Legs slender, protibiae unmodified, weakly and evenly curved, with mesal margins sinuate. Aedeagus (Figs 55 – 58) stout, weakly sclerotized, AeL 0.14 mm; median lobe in ventral view parallel-sided in median region, dorsal apical plate in ventral view broadly rounded and in lateral view abruptly, strongly bent dorsad, ventral apical plate narrower than dorsal one and with broadly rounded apex; pair of distally divergent sublateral projections is situated between plates; endophallus lacking strongly sclerotized components, symmetrical. Parameres broad and short, not reaching apex of median lobe, each with 2 long apical and several tiny subapical setae. Female. Unknown.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC46FFFBFF19FE71FDC9F844.taxon	distribution	Distribution. Japan, Kantō region: Kanagawa Prefecture (Fig. 111).	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC46FFFBFF19FE71FDC9F844.taxon	etymology	Etymology. The adjective pseudotrimerus refers to the structure of the antennal club.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC46FFFBFF19FE71FDC9F844.taxon	discussion	Remarks. This small-bodied species is similar to several undescribed Euconnus species that occur in various regions of Japan, and so far known only from females. Consequently, the aedeagus must be examined to identify E. pseudotrimerus. The dorsal apical plate broadly rounded in ventral view and sharply bent dorsad in lateral view, the pair of subapical sublateral projections between the dorsal and ventral apical plates and the structure of the endophallus are all unique for this species.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC47FFFFFF19F939FB55FE6C.taxon	description	(Figs 59 – 63, 111)	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC47FFFFFF19F939FB55FE6C.taxon	materials_examined	Type material studied. Holotype (Japan: Okinawa Prefecture: Iriomote-jima Is.): ♂, two labels: “ JAPAN, OKINAWA Pref. / Iriomote-jima, Urauchi / near Mâre-gawa river / 11 - 13. ix. 2003 / Koji & Shiho Arai leg. ” [white, printed], “ EUCONNUS s. str. / urauchianus m. / P. Jałoszyński, ’ 22 / HOLOTYPUS ” [red, printed] (NSMT). Paratypes (3 exx): ♂, same data as for holotype; 2 ♂♂, “ JAPAN, OKINAWA Pref. / Iriomote-jima, Komi / 9. vi. 2002 / T. Ishikawa leg. ”. Paratypes with yellow “ PARATYPUS ” labels similar to that with holotype, deposited in NSMT and cPJ.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC47FFFFFF19F939FB55FE6C.taxon	diagnosis	Diagnosis. Antennal club with antennomere 8 only slightly larger than 7 but much smaller than 9; head round, with vertex not bulging posterodorsad; pronotum subconical and broadest at base, with one pair of distinct antebasal pits and additional median pit (in one studied specimen, median pit situated in short transverse groove), sublateral carinae indistinct; head and protibiae in males unmodified; aedeagus weakly sclerotized, in ventral view with strongly elongate dorsal apical plate, its apex blunt, subtriangular, dorsal plate in lateral view bent distodorsad at base, with distal region straight, ventral apical plate in ventral view with bifurcate apex, additional sublateral projections between ventral and dorsal plate subtriangular, endophallic structures symmetrical but poorly defined (i. e., lacking clearly delimited sclerites).	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC47FFFFFF19F939FB55FE6C.taxon	description	Description. Body of male (Fig. 59) elongate, flattened; pigmentation moderately light brown, appendages indistinctly lighter; body covered with setae distinctly lighter than cuticle; BL 0.93 – 1.05 mm. Head smaller than pronotum, broadest at eyes, round, HL 0.18 – 0.20 mm, HW 0.18 – 0.20 mm; tempora in dorsal view about twice as long as eyes, behind eyes strongly and evenly convergent posterad, posterior margin of vertex strongly rounded, not bulging posterodorsad. Frons and vertex with unremarkable, fine punctures, glossy; setae sparse and suberect, tempora and posterior margin of vertex with dense thick bristles. Antennae short and compact, but with loosely assembled clubs, AnL 0.38 mm, scape and pedicel each only slightly elongate, antennomeres 3 ‒ 7 each transverse, 8 nearly as long as broad and only slightly enlarged in relation to 7, 9 ‒ 10 gradually broadening, both strongly transverse, 11 slightly shorter than 9 and 10 combined, about as long as broad. Pronotum subconical, broadest at base; PL 0.23 – 0.25 mm, PW 0.21 – 0.24 mm. Base with one pair of distinct antebasal pits, and additionally with median pit that is slightly larger than lateral ones (in one paratype median pit situated in short transverse groove not reaching lateral pits), sublateral carinae indistinct. Punctures and setae on disc similar to those on frons and vertex; sides of pronotum with dense thick bristles. Elytra together oval, broadest slightly in front of middle; EL 0.53 – 0.60 mm, EW 0.35 – 0.38 mm, EI 1.50 – 1.60; humeral calli small but clearly marked and each mesally demarcated by round basal elytral impression; elytral apices separately rounded. Punctures indistinct, superficial and unremarkable; setae sparse and not longer than those on pronotal disc, but slightly thicker, suberect. Legs slender, protibiae unmodified, weakly and evenly curved, with mesal margin arcuate, concave. Aedeagus (Figs 59 – 63) stout, weakly sclerotized, AeL 0.18 mm; median lobe in ventral view broadest in submedian region, dorsal apical plate in ventral view strongly elongate and with subtriangular, blunt apex, in lateral view bent distodorsally and with distal region straight, ventral apical plate broader than dorsal one and with bifurcate apex, pair of distally divergent sublateral projections is situated between plates, endophallus lacking strongly sclerotized components, symmetrical. Parameres broad and relatively long, almost reaching apex of median lobe, each with 2 long apical and two long subapical setae. Female. Unknown.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC47FFFFFF19F939FB55FE6C.taxon	distribution	Distribution. Japan, southern Ryūkyū: Iriomote-jima Is. (Fig. 111).	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC47FFFFFF19F939FB55FE6C.taxon	etymology	Etymology. The adjective urauchianus refers to the Urauchi-gawa River, one of two localities where the type series comes from.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC47FFFFFF19F939FB55FE6C.taxon	discussion	Remarks. This is another small-bodied species similar to several undescribed Euconnus spp. so far known only from females and must be identified by aedeagal structures. The uniquely bifurcate ventral apical plate, the elongate dorsal apical plate and the general shape of the median lobe allow for unambiguous determination.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC42FFFFFF19FDB2FB29F934.taxon	description	Two previously described Far Eastern species, E. taiwanus Franz, 1985 a, and E. fukiensis Franz, 1985 a, show problematic characters that so far made it impossible to decide to which subgenus of Euconnus they should be assigned. Many similar species were placed in Euconophron (currently junior synonym of Eupentarius Reitter), mainly based on the shape of the pronotum, which is round and broadest slightly behind middle. However, the pronotum does not have the median antebasal pit, typical of the type species of Eupentarius (and Euconophron, and all previously recognized subgenera that have been merged with Eupentarius). The clearly trimerous antennal club, but with the antennomere 9 distinctly smaller than 10, did not allow for placing these species in the former subgenus Napochus, which has a somewhat similar pronotum (although in its type species broadest at base). Examination of numerous specimens from Japan, primarily from the Ryūkyū, revealed that this group includes at least six externally very similar species, but showing an enormous diversity in the aedeagal structures. They are all treated here as members of the Euconnus taiwanus species group, which is characterized by the above-mentioned two features: the antennae remarkably short and compact, with trimerous clubs, but antennomere 9 always much narrower than 10; and the pronotum rounded at sides, broadest slightly behind middle or at middle, and with two pairs of antebasal pits. In addition, all members have distinctly elongate head, with strongly elevated supraantennal tubercles narrowly separated at middle and vertex slightly bulging posterodorsad; the pronotal base with two pairs of pits, of which inner pair is slightly larger than outer pair, lacking transverse groove or connected by faint, barely discernible groove; and thick bristles distributed on tempora, vertex and sides of pronotum. Aedeagi are so diverse that it is not possible to include any genital characters into the diagnosis of this group. Morphological structures of this group were studied in detail to make sure that these unusual species indeed belong in Euconnus. The following diagnostic features of Euconnus were found in E. taiwanus: the head (Fig. 64) with anteriorly situated eyes, with occipital constriction; the basisternal region of prosternum (Fig. 65) much shorter than the coxal region (= furcasternum); the procoxal cavities closed by postcoxal lobes of furcasternum and hypomera; the notosternal sutures and hypomeral ridges present; mesocoxal rests on the metaventrite (Fig. 67) separated by a keel-like, carinate mesoventral intercoxal process; and metacoxae separated by the metaventral intercoxal process. Males in this group are winged and have fully developed metanota (Fig. 66), with alacristae almost as long as length of mesoscutum + mesoscutellum. The mesoscutellar shield (Fig. 66) is not exposed between elytra in intact specimens. The following species are included in the E. taiwanus group: E. taiwanus (Taiwan), E. fukiensis (China: Fujian), and four newly described Japanese species: E. bibaculatus, E. cryptoiriomotensis, E. oitaensis, and E. banana. As the two first species were inadequately described, they are redescribed in the present paper.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC42FFFCFF19F97AFA2BF978.taxon	materials_examined	Type material studied. Holotype (Taiwan): ♂, two labels: “ Taiwan, 1400 m / Fenchihu, 10.4.77 / lg. Klapperich ” [white, handwritten], “ Euconnus / taiwanus m. / det. H. Franz ” [white, handwritten and printed], “ Holotypus ” [red, handwritten] (NHMW). Additional material examined (42 exx). Taiwan: ♂, Peinan Hsiang, Taitung Hsian, Chihpen Spa, 1 - 5.04.2004, FIT, T. Tsuru leg. (cPJ). Japan: Ishigaki-jima Is.: ♂, Banna-dake, 31.05 - 01.06.2012, T. Lackner leg. (cPH); ♂, Omoto-dake, 22.03.1984, leg. S. Nomura (NSMT); ♀, Omoto-dake, 09.04.1986, leg. S. Nomura (NSMT); 2 ♂♂, 1 ♀, Omoto-dake, 11.06.2003, H. Mizushima leg. (cPJ); 4 ♂♂, Omoto-dake, 100 m, 15 - 21.03.2004, FIT, leg. S. Nomura (NSMT); 3 ♂♂, Ura-Banna, 100 m, 21 - 23.03.2004, FIT, leg. S. Nomura (NSMT); ♂, Omoto-dake, 18.06.2002, leg. T. Tsuru (cPJ); ♂, Shiramizu, 07.03.2002, Tullgren, leg. S. Nagashima (cPJ); ♀, Shiramizu, 30 m, 15.06.2003, leg. H. Mizushima (cPJ); ♂ Kabira env., 15.01.2017, leg. P. Jałoszyński (cPJ); 2 ♂♂, 1 ♀, Omoto-dake, 17.09.2003, leg. P. Jałoszyński; ♀, Omoto-dake, 100 m, 02.01.2003, leg. P. Jałoszyński (cPJ); ♀, Nosoko-dake, 200 m, 12.06.2003, leg. H. Mizushima (cPJ); 2 ♀♀, Sokobaru Dam env., 17.01.2017, leg. P. Jałoszyński (cPJ); 3 ♂♂, “ by truck trap ”, 28.10.1996, leg. K. Takahashi (NSMT); Iriomote-jima Is.: ♂, Gunkan-Iwa, 50 m, 17 - 20.03.2004, FIT, S. Nomura leg. (NSMT); ♀, Kanpiree-no-taki waterfall, 12.09.2003, leg. S. Arai (cPJ); ♂, Kanpiree, 13.04.1986, leg. S. Nomura (NSMT); 3 ♂♂, Kanpiree, 80 m, 17 - 20.03.2004, FIT, leg. S. Nomura (NSMT); 1 ♂, 6 ♀♀, Komi, 09.06.2002, leg. T. Ishikawa (cPJ); ♀, Ôtomi-rindō, 19.06.2005, leg. T. Ishizaki (cPJ).	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC42FFFCFF19F97AFA2BF978.taxon	diagnosis	Diagnosis. Antennal club trimerous with antennomere 9 distinctly narrower than 10; males lacking secondary dimorphic features; aedeagus bottle-shaped, with short, transverse subtrapezoidal distal region; endophallus with transverse pair of symmetrical sclerotized structures in subapical region and elongate median subapical tubular component, usually showing darker inner granules.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC42FFFCFF19F97AFA2BF978.taxon	description	Description. Body of male (Figs 68, 77) elongate, strongly convex; pigmentation moderately to darkly brown, appendages indistinctly lighter except for clearly lighter tarsi and maxillary palps; body covered with setae distinctly lighter than cuticle; BL 1.26 – 1.45 mm. Head much narrower than pronotum, broadest at eyes, round, HL 0.29 – 0.33 mm, HW 0.23 – 0.26 mm; tempora in dorsal view about three times as long as eyes, behind eyes strongly and evenly convergent posterad, posterior margin of vertex strongly rounded and short, slightly bulging posterodorsad. Frons and vertex with unremarkable, fine punctures, glossy; setae sparse and suberect, tempora and posterior margin of vertex with dense thick bristles. Antennae short and compact, AnL 0.45 – 0.50 mm, scape and pedicel each distinctly elongate, antennomeres 3 ‒ 8 each slightly transverse (8 indistinctly so), 9 ‒ 11 gradually increasing in width and length, 9 and 10 each strongly transverse, 11 about as long as 9 and 10 combined, about 1.2 × as long as broad. Pronotum subconical, broadest distinctly in front of base; PL 0.35 – 0.40 mm, PW 0.35 – 0.38 mm. Base with two pairs of pits, outer pits smaller than inner ones, sublateral carinae indistinct. Punctures and setae on disc similar to those on frons and vertex; sides of pronotum with dense thick bristles. Elytra together oval, broadest clearly in anterior half; EL 0.63 – 0.75 mm, EW 0.50 – 0.55 mm, EI 1.25 – 1.45; humeral calli small but clearly marked and each mesally demarcated by small round basal elytral impression; elytral apices separately rounded. Punctures indistinct, superficial and unremarkable; setae sparse and slightly longer than those on pronotal disc, suberect. Legs slender, protibiae unmodified, weakly and evenly curved, with mesal margins slightly sinuate. Aedeagus (Figs 69 – 72: holotype, partly distorted; 73 – 76: non-type specimen from Taiwan; 78 – 80: non-type specimens from Japan) moderately stout, weakly sclerotized, AeL 0.23 mm; median lobe in ventral view in most specimens broadest in submedian region, but in some nearly parallel-sided, dorsal apical plate in ventral view short, transverse, subtrapezoidal; sclerotized ventral apical plate lacking, ventral subapical area membranous, endophallic structures symmetrical, with two lateral and one median elongate sclerites that in some specimens are partly everted (Fig. 79, indicated by arrowheads), in subapical region with pair of transverse sclerotized structures, and at middle with elongate, tubular component, usually containing inner areas of darker sclerotization visible as groups of granules. Parameres slender and short, not reaching apex of median lobe, distinctly broadened in subapical half, each with 2 – 4 long apical setae. Female. Externally indistinguishable from male. BL 1.35 – 1.46 mm; HL 0.33 – 0.35 mm, HW 0.24 – 0.28 mm, AnL 0.43 – 0.50 mm; PL 0.38 – 0.40 mm, PW 0.35 – 0.38 mm; EL 0.65 – 0.73 mm, EW 0.53 – 0.58 mm, EI 1.18 – 1.40.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC42FFFCFF19F97AFA2BF978.taxon	distribution	Distribution. Taiwan and Japan: southern Ryūkyū: Iriomote-jima and Ishigaki-jima islands (Fig. 112).	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC42FFFCFF19F97AFA2BF978.taxon	discussion	Remarks. External differences between members of the Euconnus taiwanus group may be misleading, especially in species with males not showing any secondary dimorphic features, and examination of aedeagus is necessary to identify species. Euconnus taiwanus is highly variable in terms of the body length and proportions of body parts, but the aedeagus, although it shows some variability, is distinctly different from that of any other member of this species group. As it occurs on Taiwan, Ishigaki-jima and Iriomote-jima, it can be expected to be found also on Yonaguni-jima, which is halfway between Iriomote and Taiwan and has suitable subtropical forests to maintain a rich Scydmaeninae fauna.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC41FFF2FF19F8A6FE28FBAC.taxon	materials_examined	Type material studied. Holotype (China: Fujian): ♂, three labels: “ KUATUN, FUKIEN / China 26.3.46 / (TSCHUNG SEN.) ” [white, printed and handwritten], “ Euconnus / fukiensis m. / det. H. Franz ” [white, handwritten and printed], “ Holotypus ” [red, handwritten] (NHMW).	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC41FFF2FF19F8A6FE28FBAC.taxon	diagnosis	Diagnosis. Antennal club trimerous with antennomere 9 distinctly narrower than 10; males with strongly and conspicuously modified elytra: apical region rapidly and steeply sloping down, flattened, at middle covered with extremely short, barely discernible setae, flattened area surrounded by setae much shorter and much denser than those in anterior half of elytra; aedeagus with deeply bifurcate apex, short median projection with rounded apex, and darkly sclerotized, oval subapical elongate median endophallic component.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC41FFF2FF19F8A6FE28FBAC.taxon	description	Description. Body of male (Fig. 81) elongate, strongly convex; pigmentation moderately dark brown with reddish hue, appendages indistinctly lighter except for clearly lighter tarsi and maxillary palps; body covered with setae distinctly lighter than cuticle; BL 1.75 mm. Head much narrower than pronotum, broadest at eyes, HL 0.38 mm, HW 0.33 mm; tempora in dorsal view about 2.5 times as long as eyes, behind eyes strongly and evenly convergent posterad, posterior margin of vertex strongly rounded and short, slightly bulging posterodorsad. Frons and vertex with unremarkable, fine punctures, glossy; setae sparse and suberect, tempora and posterior margin of vertex with dense thick bristles. Antennae short and compact, AnL 0.60 mm, scape and pedicel each distinctly elongate, antennomeres 3 ‒ 7 each slightly transverse (7 indistinctly so), 8 about as long as broad, 9 ‒ 11 gradually increasing in width and length, 9 as long as broad, 10 slightly transverse, 11 as long as 9 and 10 combined, about 1.3 × as long as broad. Pronotum subconical but strongly narrowing posterad and appears round, broadest at middle; PL 0.45 mm, PW 0.45 mm. Base with two pairs of pits, outer pits indistinctly smaller than inner ones, sublateral carinae indistinct. Punctures and setae on disc similar to those on frons and vertex; sides of pronotum with dense thick bristles. Elytra together oval, broadest slightly in front of middle; EL 0.93 mm, EW 0.73 mm, EI 1.28; humeral calli small, elongate, each mesally demarcated by elongate impression; elytral apices modified: apical region rapidly and steeply sloping down, flattened, at middle covered with extremely short, barely discernible setae, flattened area surrounded by setae much shorter and much denser than those in anterior half of elytra. Punctures indistinct, superficial and unremarkable; setae on anterior half of each elytron sparse and distinctly longer than those on pronotal disc, suberect. Legs slender, protibiae unmodified, weakly and evenly curved, with mesal margins slightly sinuate. Aedeagus (Figs 82 – 85) moderately elongate, moderately strongly sclerotized, AeL 0.33 mm; median lobe in ventral view broadest in sub-basal region, dorsal apical plate in ventral view bifurcate, composed of elongate lateral projections, ventral apical plate with narrow median apical projection rounded at apex, endophallic structures symmetrical, with darkly sclerotized median elongate component in apical region. Parameres slender and relatively long, nearly reaching apex of median lobe, each with 4 ‒ 5 long apical setae. Parameral base with strongly sclerotized and massive transverse bar. Female. Unknown.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC41FFF2FF19F8A6FE28FBAC.taxon	distribution	Distribution. China: Fujian.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC41FFF2FF19F8A6FE28FBAC.taxon	discussion	Remarks. This species can be easily identified by a unique male secondary sexual character: the apical region of elytra is rapidly and steeply sloping posterad, flattened and at middle covered with extremely short, barely discernible setae, the flattened area is surrounded by setae much shorter and much denser than those in anterior half of elytra. Moreover, the deeply bifurcate apex of the aedeagus is also found only in E. fukiensis among members of the E. taiwanus group.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC4FFFF0FF19FB09FA32F9C8.taxon	description	(Figs 86 – 91, 113)	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC4FFFF0FF19FB09FA32F9C8.taxon	materials_examined	Type material studied. Holotype (Japan: Okinawa Prefecture: Iriomote-jima Is.): ♂, two labels: “ JAPAN, OKINAWA Pref. / Iriomote-jima, Funaura / FIT, 11 - 18. iv. 2005 / T. Fukuzawa leg. ” [white, printed and handwritten], “ EUCONNUS s. str. / bibaculatus m. / P. Jałoszyński, ’ 22 / HOLOTYPUS ” [red, printed] (NSMT). Paratypes (29 exx): Iriomote-jima Is.: 6 ♂♂, “ JAPAN, OKINAWA Pref. / Iriomote-jima, Kanpiree / 80 m, 17 - 20. iii. 2004, FIT / S. Nomura leg. ” [white, printed]; 2 ♂♂, “ JAPAN, OKINAWA Pref. / Kanpiree, St. 1 (80 m) / Iriomote-jima / 20. iii. 2004 / leg. S. Nomura ” [white, printed]; Ishigaki-jima Is.: ♂, “ JAPAN, OKINAWA Pref. / Ishigaki-jima, Shiramizu, / 3 - 6. v. 2004 / Tomayuki Tsuru leg. FIT ” [white, printed]; 2 ♂♂, “ JAPAN, OKINAWA Pref. / Ishigakijima, Omoto-dake / 100 m, 15 - 21. iii. 2004, FIT / S. Nomura leg. A 1 ” [white, printed]; 4 ♂♂, “ JAPAN, OKINAWA Pref. / ISHIGAKI-JIMA, Kabira env. / jungle and roadside, 15 I 2017 / leg. P. JAŁOSZYŃSKI ” [white, printed]; ♂, “ JAPAN, OKINAWA Pref. / ISHIGAKI-JIMA, Sokobaru / Dam env., forest, 17 I 2017 / leg. P. Jałoszyński ” [white, printed]; 2 ♂♂, “ Mt. Omotodake / Ishigaki Is. / Okinawa Pref. ”. “ 9. iv. 1986 / S. Nomura leg ” [white, printed]; ♂, “ Mt. Omotodake / Ishigakijima Is. ”, “ 22. iii. 1984 / S. Nomura leg. ” [white, printed]; Yonaguni-jima Is.: 4 ♂♂, “ JAPAN, OKINAWA Pref. / Yonaguni-jima, Mantabaru- / shinrin-kōn, 9 - 11. iii. 2004 / Koji & Shiho Arai leg. ” [white, printed]; 3 ♂♂, “ JAPAN, OKINAWA Pref. / Yonaguni-jima, Mt. Kubura- / dake, FIT, 9 - 12. ix. 2004 / Koji & Shiho Arai leg. ” [white, printed]; 2 ♂♂, “ JAPAN, OKINAWA Pref. / Yonaguni-jima, Mt. Inbi- / dake, Tull., 10. ix. 2004 / Koji & Shiho Arai leg. ” [white, printed]; ♂, “ Mt. Kuburadake (upside) / Yonagunijima Is. / [Ryukyu, JAPAN] / 18. iii. 2005, S. Nomura leg. ” [white, printed]. Paratypes with yellow “ PARATYPUS ” labels similar to that with holotype, deposited in NSMT and cPJ.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC4FFFF0FF19FB09FA32F9C8.taxon	diagnosis	Diagnosis. Antennal club trimerous with antennomere 9 distinctly narrower than 10; males lacking secondary sexual characters; aedeagus with pair of conspicuously long sublateral projections flanking dorsal apical plate.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC4FFFF0FF19FB09FA32F9C8.taxon	description	Description. Body of male (Fig. 86) elongate, strongly convex; pigmentation moderately to darkly brown, appendages indistinctly lighter except for clearly lighter tarsi and maxillary palps; body covered with setae distinctly lighter than cuticle; BL 1.24 – 1.38 mm. Head much narrower than pronotum, broadest at eyes, HL 0.30 – 0.33 mm, HW 0.23 – 0.25 mm; tempora in dorsal view about 3 times as long as eyes, behind eyes strongly and evenly convergent posterad, posterior margin of vertex strongly rounded and short, slightly bulging posterodorsad. Frons and vertex with unremarkable, fine punctures, glossy; setae sparse and suberect, tempora and posterior margin of vertex with dense thick bristles. Antennae short and compact, AnL 0.45 – 0.50 mm, scape and pedicel each distinctly elongate, antennomeres 3 ‒ 8 each slightly transverse (8 indistinctly so), 9 ‒ 11 gradually increasing in width and length, 9 slightly and 10 strongly transverse, 11 indistinctly longer than 9 and 10 combined, about 1.3 × as long as broad. Pronotum subconical, broadest distinctly behind middle; PL 0.31 – 0.35 mm, PW 0.29 – 0.35 mm. Base with two pairs of pits, outer pits indistinctly smaller than inner ones, in some specimens faint transverse groove connects inner pits, sublateral carinae indistinct. Punctures and setae on disc similar to those on frons and vertex; sides of pronotum with dense thick bristles. Elytra together oval, broadest distinctly in front of middle; EL 0.60 – 0.70 mm, EW 0.45 – 0.50 mm, EI 1.32 – 1.47; humeral calli small, elongate, each mesally demarcated by short elongate impression; elytral apices separately rounded. Punctures indistinct, superficial and unremarkable; setae sparse and distinctly longer than those on pronotal disc, suberect. Legs slender, protibiae unmodified, weakly and evenly curved, with mesal margins slightly sinuate. Aedeagus (Figs 87 – 91) moderately elongate, moderately strongly sclerotized, AeL 0.20 mm; median lobe in ventral view broadest in submedian region, dorsal apical plate in ventral view elongate subtriangular with rounded or indistinctly truncate apex, ventral apical plate broad and short, subtrapezoidal, two pairs of elongate projections (inner and outer) are situated between ventral and dorsal plates, outer ones conspicuously long, with rounded apices; endophallic structures symmetrical, lightly sclerotized and poorly delimited. Parameres relatively broad and short, not reaching apex of median lobe, each with 3 ‒ 5 long apical setae. Female. Unknown or indistinguishable from similar species (see Remarks).	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC4FFFF0FF19FB09FA32F9C8.taxon	distribution	Distribution. Japan: southern Ryūkyū: islands Yonaguni, Iriomote and Ishigaki (Fig. 113).	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC4FFFF0FF19FB09FA32F9C8.taxon	etymology	Etymology. The adjective bibaculatus is derived from the Latin noun baculum, a stick. The specific epithet refers to the conspicuous pair of strongly elongate rod-like projections in the subapical region of aedeagus.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC4FFFF0FF19FB09FA32F9C8.taxon	discussion	Remarks. Males of this species do not have any remarkable secondary dimorphic features, and identification must be made by examination of the aedeagus. The unique pair of the elongate lateral projections of the median lobe is not known in any other members of the E. taiwanus species group. I was not able to find any external characters to distinguish E. bibaculatus from the sympatric E. cryptoiriomotensis and allopatric E. oitaensis described below. For this reason, only males are included in the type series, and females of similar body shape and length collected on the west-southernmost Japanese islands should be treated as impossible to identify by morphological features. Externally, this species is as variable in the body length and proportions of body parts as E. taiwanus. A moderate variability in the shape of the dorsal apical plate of the aedeagus was found among studied specimens. Most specimens (independently of their origins from Yonaguni-jima, Iriomote-jima or Ishigaki-jima) have the aedeagi similar to the variant shown in Figs 87 ‒ 90. In some, especially from Yonaguni, the apex is broader and more subtriangular, and the median lobe and the pair of subapical projections are slightly stouter (as in Fig. 91). However, intermediate forms were found, and it seems that all specimens belong in one species distributed on three islands.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC4DFFF6FF19F92DFC66FD68.taxon	description	(Figs 92 – 96, 114)	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC4DFFF6FF19F92DFC66FD68.taxon	materials_examined	Type material studied. Holotype (Japan: Okinawa Prefecture: Iriomote-jima Is.): ♂, two labels: “ JAPAN, OKINAWA Pref. / IRIOMOTE-JIMA, 8 km NW / Ôhara, jungle, 13 I 2017 / leg. P. JAŁOSZYŃSKI ” [white, printed], “ EUCONNUS s. str. / cryptoiriomotensis m. / P. Jałoszyński, ’ 22 / HOLOTYPUS ” [red, printed] (NSMT).	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC4DFFF6FF19F92DFC66FD68.taxon	diagnosis	Diagnosis. Antennal club trimerous with antennomere 9 distinctly narrower than 10; males lacking secondary sexual characters; aedeagus conspicuously stout, with emarginate dorsal apical plate and with ventral apical plate distinctly elongate, at base about as broad as in subapical region, with distinct constriction.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC4DFFF6FF19F92DFC66FD68.taxon	description	Description. Body of male (Fig. 92) elongate, strongly convex; pigmentation dark brown, appendages indistinctly lighter except for clearly lighter tarsi and maxillary palps; body covered with setae distinctly lighter than cuticle; BL 1.35 mm. Head much narrower than pronotum, broadest at eyes, HL 0.33 mm, HW 0.25 mm; tempora in dorsal view about 3 times as long as eyes, behind eyes strongly and evenly convergent posterad, posterior margin of vertex strongly rounded and short, slightly bulging posterodorsad. Frons and vertex with unremarkable, fine punctures, glossy; setae sparse and suberect, tempora and posterior margin of vertex with dense thick bristles. Antennae short and compact, AnL 0.45 mm, scape and pedicel each distinctly elongate, antennomeres 3 ‒ 7 each slightly transverse, 8 as long as broad, 9 ‒ 11 gradually increasing in width and length, 9 and 10 each strongly transverse, 11 as long as 9 and 10 combined, about as long as broad. Pronotum subconical, broadest distinctly behind middle; PL 0.35 mm, PW 0.33 mm. Base with two pairs of pits, outer pits barely noticeable, small and shallow, inner pair connected by barely noticeable faint transverse groove. Punctures and setae on disc similar to those on frons and vertex; sides of pronotum with dense thick bristles. Elytra together oval, broadest distinctly in front of middle; EL 0.68 mm, EW 0.50 mm, EI 1.35; humeral calli small, elongate, each mesally demarcated by short elongate impression; elytral apices separately rounded. Punctures indistinct, superficial and unremarkable; setae sparse and distinctly longer than those on pronotal disc, suberect. Legs slender, protibiae unmodified, weakly and evenly curved, with mesal margins slightly sinuate. Aedeagus (Figs 93 – 96) stout, moderately strongly sclerotized, AeL 0.18 mm; median lobe in ventral view broadest in submedian region, dorsal apical plate in ventral view emarginate at middle, ventral apical plate elongate, at base about as broad as in subapical region, broadly constricted and with blunt subtriangular apex; endophallic structures symmetrical, lightly sclerotized and poorly delimited. Parameres relatively broad and long, almost reaching apex of median lobe, each with 4 ‒ 5 long apical and subapical setae, and additionally with 3 tiny setae far from apex, on lateral surface. Female. Unknown or indistinguishable from similar species (see Remarks).	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC4DFFF6FF19F92DFC66FD68.taxon	distribution	Distribution. Japan: southern Ryūkyū: Iriomote-jima Is. (Fig. 114).	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC4DFFF6FF19F92DFC66FD68.taxon	etymology	Etymology. The adjective cryptoiriomotensis refers to the cryptic habitus and the occurrence on Iriomotejima.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC4DFFF6FF19F92DFC66FD68.taxon	discussion	Remarks. The only known male of this species is externally indistinguishable from the sympatric E. bibaculatus and allopatric E. oitaensis. The aedeagus is strikingly different from that of E. bibaculatus, but similar to that of E. oitaensis. Euconnus cryptoiriomotensis occurs on Iriomote-jima, and E. oitaensis on eastern Kyūshū, ~ 1200 km NE of Iriomote. The ventral apical plate in E. cryptoiriomotensis is elongate and at base nearly as broad as in subapical region, with distinct constriction, whereas in E. oitaensis the ventral apical plate is about as long as broad, clearly broadest at base and strongly narrowing up to the submedian region. I treat these differences as species-specific. However, additional specimens collected from islands between the known sites where these species occur may verify this hypothesis, if a morphocline in male genital structures is found.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC4BFFF5FF19FCB6FB7DFE84.taxon	description	(Figs 97 – 101, 113)	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC4BFFF5FF19FCB6FB7DFE84.taxon	materials_examined	Type material studied. Holotype (Japan: Ôita Prefecture): ♂, three labels: “ Tsukahara-kōgen / Yufuin-machi / Ôita Pref. ” [white, printed], “ [Kyushu, JAPAN] / 25. v. 1997 / Kenshi Otsuka leg. ” [white, printed], “ EUCONNUS s. str. / oitaensis m. / P. Jałoszyński, ’ 22 / HOLOTYPUS ” [red, printed] (NSMT).	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC4BFFF5FF19FCB6FB7DFE84.taxon	diagnosis	Diagnosis. Antennal club trimerous with antennomere 9 distinctly narrower than 10; males lacking secondary sexual characters; aedeagus conspicuously stout, with emarginate dorsal apical plate and with ventral apical plate as long as broad, broadest at base and strongly narrowing up to middle, then weakly narrowing to form broadly rounded apex.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC4BFFF5FF19FCB6FB7DFE84.taxon	description	Description. Body of male (Fig. 97) elongate, strongly convex; pigmentation dark brown, appendages indistinctly lighter except for clearly lighter tarsi and maxillary palps; body covered with setae distinctly lighter than cuticle; BL 1.25 mm. Head much narrower than pronotum, broadest at eyes, HL 0.30 mm, HW 0.24 mm; tempora in dorsal view about 3 times as long as eyes, behind eyes strongly and evenly convergent posterad, posterior margin of vertex strongly rounded and short, slightly bulging posterodorsad. Frons and vertex with unremarkable, fine punctures, glossy; setae sparse and suberect, tempora and posterior margin of vertex with dense thick bristles. Antennae short and compact, AnL 0.43 mm, scape and pedicel each distinctly elongate, antennomeres 3 ‒ 8 each slightly transverse, 9 ‒ 11 gradually increasing in width and length, 9 and 10 each strongly transverse, 11 indistinctly longer than 9 and 10 combined, about as long as broad. Pronotum subconical, broadest distinctly behind middle; PL 0.33 mm, PW 0.30 mm. Base with two pairs of pits, outer pits much smaller than inner pair, but sharply marked, inner pair connected by barely noticeable faint transverse groove. Punctures and setae on disc similar to those on frons and vertex; sides of pronotum with dense thick bristles. Elytra together oval, broadest distinctly in front of middle; EL 0.63 mm, EW 0.48 mm, EI 1.32; humeral calli small, elongate, each mesally demarcated by short elongate impression; elytral apices separately rounded. Punctures indistinct, superficial and unremarkable; setae sparse and distinctly longer than those on pronotal disc, suberect. Legs slender, protibiae unmodified, weakly and evenly curved, with mesal margins slightly sinuate. Aedeagus (Figs 98 – 101) stout, moderately strongly sclerotized, AeL 0.15 mm; median lobe in ventral view broadest in subapical region, dorsal apical plate in ventral view emarginate at middle, ventral apical plate as long as broad, broadest at base and strongly narrowing up to middle, then weakly narrowing to form broadly rounded apex; endophallic structures symmetrical, partly darkly sclerotized but poorly delimited. Parameres relatively broad and long, almost reaching apex of median lobe, each with 4 ‒ 5 short apical and subapical setae, and additionally with 3 tiny setae far from apex, on lateral surface. Female. Unknown.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC4BFFF5FF19FCB6FB7DFE84.taxon	distribution	Distribution. Japan: Kyūshū: Ōita Prefecture (Fig. 113).	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC4BFFF5FF19FCB6FB7DFE84.taxon	etymology	Etymology. Locotypical, after the name of Ōita Prefecture.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC4BFFF5FF19FCB6FB7DFE84.taxon	discussion	Remarks. This species is most similar to E. cryptoiriomotensis; see Remarks for the latter.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC48FFCFFF19F980FB90FF4C.taxon	description	(Figs 102 – 108, 112)	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC48FFCFFF19F980FB90FF4C.taxon	materials_examined	Type material studied. Holotype (Japan: Okinawa Prefecture: Okinawa-jima Is.): ♂, three labels: “ Mt. Nishimedake (no. 4) / (epiphytic fern: soil) / Kunigami-son, Okinawa Is. / [Ryukyus: JAPAN] / 6. vii. 2001, S. Karasawa ” [white, printed and handwritten], “ Epiphytic Fern Survey / Scydmaenidae / Euconnus sp. 3 / P. Jałoszyński det., 2005 ” [orange, printed], “ EUCONNUS s. str. / banana m. / P. Jałoszyński, ’ 22 / HOLOTYPUS ” [red, printed] (NSMT). Paratypes (9 exx): Okinawa-jima Is.: 1 ♂, 2 ♀♀, same data as for holotype; ♂, same data but 27. ii. 2003; 2 ♂♂, “ Ie-rindō / Kunigami-son / Okinawa Pref. ” [white, printed], “ 16. iii. 1985 / S. Nomura leg. ”; ♂, “ (RYUKYUS) / Mt. Yonahadake / Okinawa Island / 6. X. 1978 / K. Ishikawa ” [white, printed], “ collected from / soil by using / Berlese funnel ” [white, printed]; 2 ♂♂, “ JAPAN, OKINAWA Island / Nago City, Nago Castle Site, / ~ 100 m, humid forest / 07.02.2019 / leg. P. JAŁOSZYŃSKI ” [white, printed]. Paratypes with yellow “ PARATYPUS ” labels similar to that with holotype, deposited in NSMT, EUMJ and cPJ.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC48FFCFFF19F980FB90FF4C.taxon	diagnosis	Diagnosis. Antennal club trimerous with antennomere 9 distinctly narrower than 10; males with modified mesotarsi: tarsomeres 3 and 4 each with ventral subtriangular denticle, tarsomere 5 conspicuously curved; aedeagus moderately elongate, with dorsal apical plate broadest in proximal 3 / 4 and with rounded sides, in distal 1 / 4 abruptly narrowed to form small subrectangular apical projection, ventral apical plate with broadly concave and broad distal margin, much broader than dorsal plate; endophallus with asymmetrical median sclerites.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC48FFCFFF19F980FB90FF4C.taxon	description	Description. Body of male (Fig. 102) elongate, strongly convex; pigmentation dark brown, appendages indistinctly lighter except for clearly lighter tarsi and maxillary palps; body covered with setae distinctly lighter than cuticle; BL 1.45 – 1.53 mm. Head much narrower than pronotum, broadest at eyes, HL 0.33 – 0.34 mm, HW 0.26 – 0.30 mm; tempora in dorsal view about 2.5 times as long as eyes, behind eyes strongly and evenly convergent posterad, posterior margin of vertex strongly rounded and short, slightly bulging posterodorsad. Frons and vertex with unremarkable, fine punctures, glossy; setae sparse and suberect, tempora and posterior margin of vertex with dense thick bristles. Antennae short and compact, AnL 0.53 – 0.63 mm, scape and pedicel each distinctly elongate, antennomeres 3 ‒ 8 each slightly transverse, 9 ‒ 11 gradually increasing in width and length, 9 and 10 each strongly transverse, 11 slightly longer than 9 and 10 combined, about 1.3 × as broad. Pronotum subconical but strongly narrowing posterad and with broadest site at middle or indistinctly behind middle; PL 0.40 – 0.45 mm, PW 0.38 – 0.41 mm. Base with two pairs of pits, outer pits much smaller than inner pair, but sharply marked, inner pair connected by barely noticeable faint transverse groove or not connected. Punctures and setae on disc similar to those on frons and vertex; sides of pronotum with dense thick bristles. Elytra together oval, broadest slightly in front of middle; EL 0.73 – 0.78 mm, EW 0.55 – 0.58 mm, EI 1.30 – 1.41; humeral calli small, elongate, each mesally demarcated by short round impression; elytral apices separately rounded. Punctures indistinct, superficial and unremarkable; setae sparse and distinctly longer than those on pronotal disc, suberect. Legs slender, protibiae unmodified, weakly and evenly curved, with mesal margins slightly sinuate, mesotarsi modified (Figs 103 ‒ 104): tarsomeres 3 and 4 each with ventral subtriangular denticle, tarsomere 5 conspicuously curved. Aedeagus (Figs 105 – 108) moderately elongate and strongly sclerotized, AeL 0.38 mm; median lobe in ventral view broadest in submedian region, dorsal apical plate broadest in proximal 3 / 4 and with rounded sides, in distal 1 / 4 abruptly narrowed to form small subrectangular apical projection, ventral apical plate with broadly concave and broad distal margin, much broader than dorsal plate; endophallus with asymmetrical and strongly elongate median sclerites, two sclerites in subapical region strongly divergent laterodistad. Parameres slender, not reaching apex of median lobe, partly fused to walls of median lobe in proximal half, each with 5 apical setae of various lengths. Female. Externally differs from male in unmodified mesotarsi. BL 1.43 – 1.48 mm; HL 0.33 mm, HW 0.25 mm, AnL 0.53 – 0.55 mm; PL 0.40 – 0.43 mm, PW 0.38 mm; EL 0.70 – 0.73 mm, EW 0.58 mm, EI 1.22 – 1.26.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC48FFCFFF19F980FB90FF4C.taxon	distribution	Distribution. Japan: Okinawa Prefecture: Okinawa-jima Is. (Fig. 112).	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC48FFCFFF19F980FB90FF4C.taxon	etymology	Etymology. The name banana (noun in apposition) refers to the curved, banana-like terminal mesotarsomere in males.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC48FFCFFF19F980FB90FF4C.taxon	discussion	Remarks. Males of this species can be easily identified by the modified mesotarsi, with conspicuously curved tarsomere 5. Also the aedeagus of E. banana is remarkably different from copulatory organs in the remaining members of this group. Females can be matched to males if collected together on the same spot; the known distribution of this species does not overlap with any similar species. However, the aedeagus must always be examined, because yet undescribed similar species may occur on Okinawa-jima and surrounding islands.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC71FFCCFF19FF51FDAEF978.taxon	discussion	Casey placed as a junior synonym of Euconnus s. str.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC71FFCCFF19FF51FDAEF978.taxon	description	Findings of East Palaearctic (all Japanese) species with clearly trimerous clubs, as E. kirin, E. yaimanus and E. uchinaanchu, makes this sole antennal feature to define Psomophus even more problematic. These species have aedeagi remotely similar to those of the above-mentioned Psomophus species, more resembling those of the former subgenus Napochus Thomson, which is now a junior synonym of Euconnus s. str. These three Japanese species are undoubtedly closely related one to another, as they share unusual cephalic modifications in males, not known in any Psomophus (weakly expressed but present in E. uchinaanchu), slender and strongly convex body form, endophalli with subapical median groups of elongate sclerites, and parameres with numerous setae of various lengths. The shapes of pronota differ among the E. kirin group ‒ almost subconical and broadest behind middle in E. kirin and E. yaimanus, but nearly round and broadest very indistinctly behind middle in E. uchinaanchu. All features except for the trimerous antennae place the E. kirin group in Euconnus s. str. While exploring further the Japanese fauna of Euconnus, I encountered another group of species that makes the diagnosis of Psomophus even more problematic. Euconnus pseudotrimerus and E. urauchianus are similar to each other in having a ‘ Napochus - like’ body form (i. e., the subconical pronotum and large antennal clubs almost as long as half-length of antenna) and also in the ‘ Napochus - like’ form of the aedeagus (especially in having a pair of distal lateral projections between the ventral and dorsal apical plates, near the apex of the former). However, the antennal club in E. pseudotrimerus is not exactly tetramerous. The antennomere 8 is so small that it could be interpreted as indistinctly tetramerous or indistinctly trimerous. This problem is even greater in the case of E. urauchianus, which has the three terminal antennomeres clearly enlarged and sharply demarcated, but the antennomere 8 is still somewhat enlarged, although it is only indistinctly broader than antennomere 7. Whether such a club should be treated as trimerous or tetramerous, depends on interpretation. If E. urauchianus is placed in Psomophus, then the ‘ trimerous club’ would become a highly unclear diagnostic feature for this subgenus. I prefer to remove this problematic feature (i. e., the number of antennomeres forming the club) from the diagnosis of Psomophus. This leaves no reliable characters to define Psomophus, and consequently, Psomophus is placed as a junior synonym of Euconnus s. str. Discussion concerning another group of eastern Asian Euconnus spp. with trimerous antennal clubs, the E. taiwanus group, is given below, as these species, apart from the unusual antennal structure, resemble members of the subgenus Eupentarius Reitter.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC71FFC2FF19F8BDFC89FBC0.taxon	discussion	(= Euconophron Reitter) placed as a junior synonym of Euconnus s. str.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC71FFC2FF19F8BDFC89FBC0.taxon	description	As discussed previously (Jałoszyński 2017 b), the diagnosis of Eupentarius is somewhat unclear. Better known under its junior synonymic name Euconophron, this subgenus was originally based on characters with no true taxonomic value, known today to be highly variable: elytral bases broader than the pronotal base and bearing distinct basal impressions and the ‘ humeral fold’ (i. e., the elongate humeral callus demarcated mesally by impression); the antennal club tetramerous and not sexually dimorphic; the head and pronotum similarly setose; and the pronotum with a transverse antebasal groove (Reitter 1909). Later, in one of the early papers by Franz (1957), in an attempt to ‘ save’ Euconophron, this diagnosis was modified to include large, coarsely faceted eyes; bristles on the posterior portion of the head capsule; the pronotum not much broader than the head; the anterior portion of the pronotal disc with a heart-shaped field of a translucent cuticle; the pronotal base with a transverse groove accompanied by four antebasal pits, lacking median carina; the elytra behind the (not visible) scutellum often flattened, not evenly convex; and the aedeagus always with a bifid apex, with plate-like or tooth-like endophallic sclerites. As the diagnosis of Euconophron still remained highly problematic, it was further discussed by Vít (2005), in another attempt to justify the existence of this problematic taxonomic entity. He noticed that western Palaearctic species have a uniquely shaped, deeply emarginate or bifurcate aedeagal apex. All these features were discussed in Jałoszyński (2017 b), and most of them were found irrelevant as they were too variable within Euconnus. The latter author concluded that: “ At least European species of Euconophron share unique characters that suggest that they may form a monophyletic unit and justify a placement of Euconophron as a separate subgenus of Euconnus. These characters include: i) extremely long and slender mandibles with very short basal part and one submedian mesal tooth; ii) the pronotum with a distinct median pit; iii) the prosternum with subtriangular lateral lobes projecting anteriorly in front of procoxae; iv) and the apical portion of aedeagus deeply emarginated / bifurcated. ” The situation is further complicated by the fact that Franz 1957 ‘ redescribed’ the type species of Euconophron based on most likely misidentified material, and the holotype is a female (discussed in detail by Jałoszyński (2017 b )). For this reason, it was not possible to verify whether the bifurcate aedeagal apex, the presumed diagnostic feature of Euconophron, occurs in its type species. All the above-mentioned authors (including myself) made efforts to preserve this subgenus as a separate taxonomic unit, despite the Reitter’s very first diagnosis having been already demonstrated to be entirely useless to define a genus-group taxon. The reason was the same as that behind maintaining for such a long time similarly unclear subgenera, as Napochus or Pycnophus (Jałoszyński 2021 a) ‒ in Europe these subunits of Euconnus seemed to be so distinct and so different one from another that efforts were made not to merge them into larger and more diverse units. However, such an approach fails when extra-European Euconnus species are considered. Four clearly defining characters listed above seem sufficient to maintain Eupentarius (placed as a senior synonym of Euconophron only recently; see Jałoszyński (2021 b )). However, morphological features of the newly revised East Palaearctic Euconnus taiwanus group diffuse such a diagnosis. The long mandibles with short basal portions and single submedian mesal tooth are hardly useful to define a subgenus, as the mandibular structure within Euconnus is extremely diverse. Even within European ‘ Psomophus ’ or Tetramelus Motschulsky, a great diversity of structures was illustrated (e. g., Orousset (2015, 2018 )). The form of mandible thought to be unique for Eupentarius can be found e. g., in E. (Tetramelus) pandellei (Fairmaire, 1859). The median pronotal pit seemed to be unique for Eupentarius. However, this pit can be a remainder of the reduced transverse antebasal groove and it certainly cannot be a sole diagnostic character. It was found e. g., in the newly described E. urauchianus, which does not have any other diagnostic features of Eupentarius. The prosternal lateral subtriangular lobes projecting to a various extent anteriorly in front of procoxae were demonstrated to occur also in Androconnus Franz, Cladoconnus Reitter, Tetramelus and at least some species of Euconnus s. str. (Jałoszyński 2021 b). The apical portion of the aedeagus deeply emarginate or bifurcate seemed the strongest diagnostic feature supporting a separate status of Eupentarius, until the revision of the E. taiwanus species group presented herein. The E. taiwanus group is very interesting in terms of character variability. Its species externally resemble European Euconnus previously placed in Eupentarius / Euconophron in the shape of the pronotum, which is narrowing both posterad and anterad, but with the posterior margin much longer than the anterior one. However, they do not have the median antebasal pronotal pit. The lateral prosternal lobes are developed and subtriangular, clearly projecting anterad. The antennal club, typically tetramerous in Eupentarius (unless unusually modified in males, which may have pentamerous clubs), is, however, clearly trimerous. Interestingly, unlike the club in the ‘ true Psomophus ’, i. e., the E. callidus species group, antennae are strikingly short in relation to the body and the antennomere 9 is of intermediate size between 8 and 10. Although externally this group is extremely uniform and includes some species pairs that can be distinguished only by the aedeagus, the male genital structures are unexpectedly diverse. The aedeagus of E. taiwanus has truncate or indistinctly concave apex; in E. fukiensis the apex is strongly bifurcate (like in many species included in Eupentarius); in E. bibaculatus the apex is narrow and subtriangular, convex, while in E. cryptoiriomotensis and E. oitaensis the dorsal apical plate that forms the aedeagal apical region is extremely short and shallowly emarginate. In E. banana, which otherwise is very similar to other species of the E. taiwanus complex, the aedeagus is unlike any other within this group, strongly sclerotized, with apically convex dorsal apical plate, apically concave ventral apical plate, asymmetrical endophallic sclerites, and even parameres unusually fused with the median lobe along their proximal ventral margins (a highly unusual feature for Euconnus). Moreover, the aedeagus of E. bibaculatus bears a pair of unique lateral distal projections, not known in any other species of this group. The male secondary sexual characters are also unusual. They are present only in E. fukiensis (steeply sloping and modified elytral apex) and in E. banana (strongly curved terminal mesotarsomere and ventral denticles on mesotarsomeres 3 and 4). Euconnus fukiensis is closest to the diagnosis of Eupentarius: it has two out of four characters defining that subgenus: the lateral lobes of the prosternum and the bifurcate aedeagal apex. On the other hand, the trimerous antennal club would place it (and all remaining species of the E. taiwanus group) in Psomophus, even though all these species are strikingly dissimilar to E. callidus. There are two possible actions available to avoid placing species of the E. taiwanus group as Euconnus incertae sedis (the most undesirable solution, which would only increase the chaos in Euconnus): (i) to merge Euconnus s. str., Psomophus and Eupentarius into one taxonomic entity, or (ii) to propose a new subgenus. The latter option is hardly possible because of lack of reliable diagnostic features. The E. taiwanus group is defined by the antennae remarkably short and compact, with trimerous clubs (the feature overlapping with the diagnosis of Psomophus), but the antennomere 9 always much narrower than 10; the pronotum rounded at sides, broadest slightly behind middle or at middle, and with two pairs of antebasal pits (this feature can be found in other subgenera, especially in Euconnus s. str.). All members have a distinctly elongate head, with strongly elevated supraantennal tubercles narrowly separated at middle and the vertex slightly bulging posterodorsad; the pronotal base with two pairs of pits, of which inner pair is slightly larger than outer pair, lacking transverse groove or connected by faint, barely discernible groove; and thick bristles distributed on tempora, vertex and sides of pronotum. Aedeagi are so diverse that it is not possible to include any genital characters into the diagnosis of this group. Founding a new subgenus on such a combination of characters does not seem to solve any taxonomic problems within Euconnus. Consequently, I propose here not only to place Psomophus as a junior synonym of Euconnus. s. str., but also Eupentarius as a junior synonym of Euconnus s. str.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC7FFFC2FF19FB7CFEBEFACC.taxon	type_taxon	Type species: Euconnus bechyneae Franz, 1986 c (des. orig.).	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC7FFFC2FF19F9B8FEBEF900.taxon	type_taxon	Type species: Euconnus laticlava Franz, 1992 (des. orig.).	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC7FFFC2FF19F948FD23F8B0.taxon	type_taxon	Type species: Scydmaenus motschulskii Sturm, 1838 (des. by Franz in Newton & Franz (1998 )).	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC7FFFC2FF19FA0CFE3CF990.taxon	type_taxon	Type species: Euconnus tindoui Franz, 1971 (des. orig.). Synonymized with Sciacharis s. str. by Franz, 1986 a; reinstated as subgenus of Euconnus by Jałoszyński & Newton, 2017.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC7FFFC0FF19F8D8FC30FCC4.taxon	type_taxon	Type species: Euconnus hypertrophicus Franz, 1962 (des. by Franz, 1998 (in Newton & Franz (1998 )). Synonymized with Napochus by Jałoszyński (2017 d).	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC7FFFC0FF19F8D8FC30FCC4.taxon	type_taxon	Type species: Euconnus sphaerocephalus Franz, 1980 (des. orig.). Synonymized with Pycnophus by Franz (1985 b).	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC7DFFC0FF19FA60FEBEF9C8.taxon	type_taxon	Type species: Euconnus perplexus Franz, 1986 c (des. orig.).	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC7DFFC0FF19FB94FB79FB38.taxon	type_taxon	Type species: Cytoscydmus kolbei L. W. Schaufuss in Schaufuss (1890) (des. orig.). Placed as subgenus of Euconnus by Jałoszyński, 2020.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC7DFFC0FF19FB40FEBEFAA8.taxon	type_taxon	Type species: Euconnus gomyanus Franz, 1986 b (des. orig.).	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC7DFFC0FF19FAD0FC38FA58.taxon	type_taxon	Type species: Oneila heterocera Péringuey, 1899 (des. Franz in Newton & Franz (1998 )). Placed as subgenus of Euconnus by Jałoszyński, 2020.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC7DFFC7FF19F9F0FCD3FEFC.taxon	type_taxon	Type species: Scydmaenus oblongus Sturm, 1838 (des. by Franz in Newton & Franz, 1998).	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
103A87D9FC7AFFC6FF19FE3EFA20FDFC.taxon	discussion	The subgeneric division of Euconnus, or even limits of the genus, are still problematic. The Malagasy Madagassoconnus seems to be derived from the continental African Tetramelus, and Oneila may only be a species group within Tetramelus. The endemic New Caledonian Austroconophron seems to be a good candidate to merge with Euconnus s. str., as it does not have any peculiar characters to maintain it as a separate subgenus. New intermediate forms may be found and some of the existing subgenera may require merging into one. Some subgenera are defined mainly or exclusively by male dimorphic features and females cannot be placed to subgenus. Such subgenera may in fact represent species groups derived from within Euconnus s. str. Moreover, some described species of Euconnus not placed to subgenus show a unique set of features that may justify proposing a new subgenus, e. g. a large group of Sri Lankan species including and similar to E. mutabilis Franz, 1982. Such species in the key would very likely go to Euconnus s. str. For these reasons, the key should be treated as a summary of the hitherto made changes in the classification of Euconnus, pending further study. The same key with illustrated morphological structures is given in Figs 115 – 117. The key, already in its current form, has a serious flaw. Euconnus kraatzi, previously placed in Psomophus, and now in Euconnus s. str., has the pronotum broadest clearly in front of middle. This species is not possible to place to subgenus using the key presented below, and there may be more similar Euconnus spp. Euconnus kraatzi seems to be an intermediate form between Euconnus s. str. and the subgenus Tetramelus, and in future these subgenera may be merged. The European Tetramelus species are wingless, and consequently they have reduced humeral structures of the elytra. Their antennal clubs are either gradually thickened or with tetramerous clubs, and their pronotal structures and mouthparts are relatively diverse (e. g., Orousset 2015). Outside Europe, especially in Africa and Australia, there are species that are highly similar to the European Tetramelus but winged, and therefore the silhouette of their elytra is clearly different, because the humeral calli are strongly developed. Tetramelus may only be a group (or several unrelated groups) within Euconnus s. str. This problem requires further study, preferably by molecular methods. Although I prefer in the present study not to go as far as merging Tetramelus with Euconnus s. str. (even though there are firm morphological reasons), the fact that it was impossible to construct a key to subgenera that would not allow for exceptions (as E. kraatzi) clearly demonstrates that the subgeneric system of Euconnus is still impractical and very likely does not reflect phylogenetic relationships. It is presented nevertheless, as a starting point for future work. There is another reason to publish a ‘ flawed’ key. Most of the problematic species, as E. kraatzi, would be impossible to key out, and when such a case is encountered, it may mean that the species in question is particularly interesting. For instance, it may show some intermediate or unusual characters. Such species may in fact prove to be indispensable for further study of Euconnus, one of the largest genera of any organisms on Earth. The key below can help identifying such interesting, problematic species, and this is one of its intended functions.	en	Jałoszyński, Paweł (2022): Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae). Zootaxa 5194 (3): 343-391, DOI: https://doi.org/10.11646/zootaxa.5194.3.2
