identifier	taxonID	type	CVterm	format	language	title	description	additionalInformationURL	UsageTerms	rights	Owner	contributor	creator	bibliographicCitation
FDA6A7FE59DA5F958FAC11E5C585494E.text	FDA6A7FE59DA5F958FAC11E5C585494E.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Spinoncaea humesi Boettger-Schnack 2003	<html xmlns:mods="http://www.loc.gov/mods/v3">
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            <p> 
Spinoncaea humesi 
Boettger-Schnack
, 2003
 Figs 12, 13, 14, 15 </p>
            <p> Spinoncaea humesi Böttger-Schnack , 2003: 208-215, figs 8-11 (Red Sea, Mediterranean, Indian and Pacific oceans). </p>
            <p>Material examined.</p>
            <p>
                 (1)   
                <a title="Search Plazi for locations around (long 128.26083/lat 33.74736)" href="https://tb.plazi.org/GgServer/search?materialsCitation.longitude=128.26083&amp;materialsCitation.latitude=33.74736">Northeastern Pacific</a>
                 , 9°52'1.38"N, 131°45'38.28"W (EP-2), 19 March 2019. Three females dissected on three or seven slides, respectively. Two dissected females (NIBRIV0000882796-882797) and two undissected females (in alcohol, NIBRIV0000882798) were deposited in the NIBR. (2) Northwestern Pacific (a) 13°23'46.44"N, 143°55'0.60"E (WP-1), 27 March 2016: Two males dissected on one or three slides, respectively. All dissected specimens (NIBRIV0000882799-882800) were deposited in the NIBR. (b) 13°20'3.42"N, 144°20'2.7"E (WP-2), 4 April 2016. One undissected male in alcohol (NIBRIV0000882801) was deposited in the NIBR. (3) Korea Strait, 33°44'50.50"N, 128°15'39.02"E (KS), 7 October 2008: One dissected male (NIBRIV0000882802) on H-S slide, and one undissected female and one undissected male in alcohol vial (NIBRIV0000882803) were deposited in the NIBR  . 
            </p>
            <p>Description.</p>
            <p> Female (Figs 12 - 14, Tables 3, 4). Body length in lateral view (telescoping of somites not considered) (Fig. 12B) 344-348  µm in northeastern Pacific (Table 3), somewhat larger than in the Red Sea (310-320  µm ,  Böttger-Schnack 2003: 208). </p>
            <p> Prosome 1.7  × length of urosome, excluding caudal rami, 1.3-1.4  × urosome length including caudal rami (Fig. 12B, Table 3), for comparison with Red Sea see under  “Remarks” . Integumental pores on prosome difficult to discern, not figured. </p>
            <p> P5-bearing somite with three paired midventral spinous processes (Fig. 12D), no variation in number found (but see under  “Male” ). </p>
            <p> Genital double-somite (Fig. 12C, D, E) 2  × as long as maximum width in specimen figured (measured in dorsal aspect) and ~ 1.5  × as long as postgenital somites combined; variation in length to width ratio given in Table 3, respective ratios from Red Sea specimens fit into this range; ornamentation of dorsal and ventral surfaces (Fig. 12D, E) as for Red Sea specimens, including weakly developed undulate hyaline frill on posterior margin of genital double-somite and postgenital somites, as well as absence of pores on lateral surface of postgenital somites (Fig. 12E). </p>
            <p> Anal somite (Fig. 12C) with length to width ratio 1.2-1.3 (Table 3), similar to Red Sea, but slightly different from other areas reported in  Böttger-Schnack's account (1.0-1.2:1,  Böttger-Schnack 2003: table 7). One pair of secretory pores present dorsally near posterior margin (Fig. 12C), second pair reported for Red Sea specimens not discerned. Other ornamentation as figured (Fig. 12C-E). </p>
            <p> Caudal ramus (Fig. 12A, C) 2.3-2.5  × longer than wide measured along inner margin and ~ 2.8-3.1  × longer than wide measured along outer margin (Table 3), range of variation similar to ratios reported for Red Sea and other regions (  Böttger-Schnack 2003: table 7). Length ratios among setae II, III, and IV with ranges in Pacific specimens given in Table 3, Red Sea data fit into these ranges; seta V missing on both sides of specimen figured (measurements taken from undissected specimen as follows: seta V ~ 2.7  × longer than seta IV, 1.5  × longer than seta VII). </p>
            <p> Antennule (Fig. 13A) with armature formula as for  S. ivlevi . Ornamentation along inner non-setiferous margin of segments 2 and 3 absent, as specified for Red Sea specimens. </p>
            <p> Antenna 3-segmented, armature and ornamentation as figured (Fig. 13B). Endopod segments ~ equal in length (but in Fig. 13B, the proximal endopod segment looks shorter than the distal one, due to its orientation on the slide); distal endopod segment ~ 4  × longer than wide, variation given in Table 3, Red Sea data fit into these ranges; armature and ornamentation as in  S. ivlevi , except for seta II slightly longer than seta I (for numbering of elements see Fig. 3B). </p>
            <p> Labrum with ornamentation as figured (Fig. 13G) including difference to  S. ivlevi in size of four marginal teeth along distal (ventral) margin on each lobe being smaller than in  S. ivlevi . Posterior face with two secretory pores on each lobe, which are difficult to discern. Anterior surface of labrum not observed in detail, but overlapping rows of fine spinules covering median concavity on anterior side visible from Fig. 13G. </p>
            <p>Mandible with armature and ornamentation as figured (Fig. 13C), small element D on gnathobase absent, as typical for the species.</p>
            <p> Maxillule (Fig. 13D) similar to  S. ivlevi , except for middle element on outer lobe naked. </p>
            <p>Maxilla with armature and ornamentation as figured (Fig. 13E), additional ornamentation on syncoxa in Pacific specimens arrowed in Fig. 13E.</p>
            <p>Maxilliped with armature and ornamentation as figured (Fig. 13F), similar to Red Sea specimens, including small ornamentation details, such as proximal element on basis unornamented.</p>
            <p> Swimming legs (Fig. 14A-D), with armature as in  S. ivlevi except for spine count on distal exopod segment of P2, showing only two outer spines (Table 2). Intercoxal sclerites unornamented (missing in specimen figured). Surface of coxae and bases with sparse surface ornamentation as figured, outer basal seta on P4 very long, reaching as far as tip of distal exopod segment (Fig. 14D), as typical for the species. </p>
            <p>Exopods with variability of proportional spine lengths in Pacific specimens given in Table 4, respectively values from Red Sea generally fit into these ranges, except proportional spine lengths on P2 larger than in the Red Sea specimens.</p>
            <p> Endopods with length ranges of outer subdistal spine and outer distal spine relative to distal spine on P2 and P4 given in Table 4 generally similar to Red Sea specimens, except for outer distal spine relative to distal spine on P2 (0.45-0.51) and P3 (0.42-0.44) smaller than Red Sea (0.56 on P2 and 0.48 on P3, calculated from  Böttger-Schnack 2003: fig. 10B, C). </p>
            <p> P5 (Fig. 12C, E) with exopod 1.4  × longer than wide, shorter than in Red Sea (1.7:1; cf.  Böttger-Schnack 2003: 208, fig. 8H, I), armature and ornamentation as figured. </p>
            <p>P6 (Fig. 12C) as figured, armature (short spinule) difficult to discern.</p>
            <p> Male (Fig. 15, Tables 3, 4). Body length 285-295  µm (Table 3). Sexual dimorphism in antennule, maxilliped, P6, and in genital segmentation, slight modification in setal length of P5. Pore pattern on prosome not discerned. </p>
            <p>P5-bearing somite with paired midventral spinous processes variable in number (two or three processes) (Fig. 15D).</p>
            <p> Caudal rami (Fig. 15A, C, D) with length to width ratio 2.1-2.5 measured along inner margin and 2.6-3.2 measured along outer margin (Table 3), [single value from Korea Strait larger than those from western equatorial Pacific,] respective values from Red Sea and other areas (  Böttger-Schnack 2003: table 7) fit into this range. Ornamentation details as figured, similar to Red Sea specimens, including absence of surface ornamentation on genital somite (Fig. 15C, D). </p>
            <p> Antennule (Fig. 15F) with armature as for  S. ivlevi . Segments 2 and 3 without ornamentation. </p>
            <p>Maxilliped (Fig. 15G, H) 3-segmented, syncoxa missing in specimen figured. Basis and endopod (claw) with armature and ornamentation similar to Red Sea specimen, including ornamentation detail on claw, with pinnules only along distal half of concave margin.</p>
            <p>Swimming legs 1-4 with the value ranges in spine lengths on rami given in Table 4 not significantly different from female, except for the values of the endopodal spines on P4 from Korea Strait smaller than those of females.</p>
            <p> P5 (Fig. 15B, E) with exopodal seta and outer basal seta shorter than in female, outer basal seta also much shorter than in Red Sea specimens (  Böttger-Schnack 2003: fig. 11D-F). </p>
            <p>P6 (Fig. 15D) with ornamentation as figured.</p>
            <p>Remarks.</p>
            <p> The morphology of both sexes of  S. humesi from the Pacific agrees in most parts with the original description of the species by  Böttger-Schnack (2003). As stated above, the Pacific specimens differ only in a few characters, such as in (1) a somewhat larger body size in the female and (2) the length ratio of the prosome to the urosome in the female, which appears to be slightly larger in the Pacific specimens (1.7:1 and 1.3-1.4:1, excluding and including caudal rami, respectively) as compared to the Red Sea specimens (1.5:1 excluding caudal rami and 1.2:1 including caudal rami, calculated from  Böttger-Schnack (2003: fig. 8A). Note, that in the text of  Böttger-Schnack (2003: 208) the proportions of the prosome to the urosome are given as 2.0:1 and 1.7:1, respectively, but these were calculated by a different method taking into account the telescoping of somites, while the telescoping of somites was not considered in the present study. Also, some additional ornamentations were found in the Pacific specimens, such as on the syncoxa of the maxilla of both sexes, the additional ornamentation on the inner portion of the basis of P2-P4 in our Pacific specimens or the number and size of spatulated spinules between proximal seta and articulation with endopod on the maxilliped in female, which are smaller and more numerous than in the specimen from the Red Sea. </p>
            <p> The male of  S. humesi from the Korea Strait agreed in almost all morphological characters with the specimens from the northwestern equatorial Pacific. But it exhibited individual variabilities in the length to width ratio of caudal ramus, the relative length ratio of caudal setae, and the length to width ratio of the genital somite (cf. Tables 3, 4). An additional variation in the male from the Korea Strait was found in the number of midventral spinous processes on the P5-bearing somite, with three paired processes (not figured), as in female, while in the male of the northwestern Pacific only two paired processes were found, as in the male from the Red Sea (  Böttger-Schnack 2003: fig. 11E). The number of midventral spinous processes on the P5-bearing somite seems to be a common individual variation seen within both sexes among  Spinoncaea species. </p>
            <p> Spinoncaea humesi can easily be distinguished from the other two species of  Spinoncaea by the number of spines on P2exp-3, showing two outer spines in  S. humesi , but three spines in  S. ivlevi and  S. tenuis . Also, the outer basal seta of P5 is extremely long, extending beyond the posterior margin of the genital double-somite in the female, and the shape of genital double-somite is different, being barrel-shaped in  S. humesi . Other additional characters for species segregation are not further mentioned in the present study because they are described in detail in the remarks section of  S. humesi by  Böttger-Schnack (2003: 214-215). </p>
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	https://treatment.plazi.org/id/FDA6A7FE59DA5F958FAC11E5C585494E	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Cho, Kyuhee;Park, Chailinn;Boettger-Schnack, Ruth	Cho, Kyuhee, Park, Chailinn, Boettger-Schnack, Ruth (2021): Taxonomy of three species of the genus Spinoncaea (Copepoda, Oncaeidae) in the North Pacific Ocean with focus on morphological variability. ZooKeys 1043: 147-191, DOI: http://dx.doi.org/10.3897/zookeys.1043.64438, URL: http://dx.doi.org/10.3897/zookeys.1043.64438
E63B3C5F7FA2574CA9783806118B21F6.text	E63B3C5F7FA2574CA9783806118B21F6.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Spinoncaea ivlevi (Shmeleva 1966)	<html xmlns:mods="http://www.loc.gov/mods/v3">
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            <p> Spinoncaea ivlevi (Shmeleva, 1966) Figs 2, 3, 4, 5, 6, 7, 16 </p>
            <p> Oncaea ivlevi Shmeleva, 1966: 932-933, figs 1.1-1.11 (Adriatic). </p>
            <p> Oncaea ivlevi : Shmeleva 1969: 5-8, 27, figs 3a-i, 4a-h (Adriatic, tropical Atlantic). </p>
            <p> Oncaea ivlevi : Malt 1982: 186-187, 193, figs 3a-k, 4a-d (temperate Atlantic). </p>
            <p> Spinoncaea ivlevi :  Böttger-Schnack 2003: 193-207, figs 2-7 (Red Sea, Mediterranean Sea, Indian and Pacific oceans). </p>
            <p>Material examined.</p>
            <p>
                 1. Robust form. (1) Northwestern Pacific (a)   13°23'46.44"N, 143°55'0.60"E (WP-1), 27 March 2016: Five females and four males dissected on several slides, respectively.  
                <a title="Search Plazi for locations around (long 143.91684/lat 13.396234)" href="https://tb.plazi.org/GgServer/search?materialsCitation.longitude=143.91684&amp;materialsCitation.latitude=13.396234">Four</a>
                 dissected females (NIBRIV0000882743-882746) and four dissected males (NIBRIV0000882747-882750) were deposited in the NIBR; (b)   13°20'3.42"N, 144°20'2.7"E (WP-2), 4 April 2016: Six females dissected on several slides, respectively. Four dissected females (NIBRIV0000882751-882754), one undissected female (NIBRIV0000882755) and one undissected male (NIBRIV0000882756) mounted on H-S slide, respectively, and five undissected females and three undissected males in alcohol vial (NIBRIV0000882757) were deposited in the NIBR. (2)  
                <a title="Search Plazi for locations around (long 144.33408/lat 13.334283)" href="https://tb.plazi.org/GgServer/search?materialsCitation.longitude=144.33408&amp;materialsCitation.latitude=13.334283">Northeastern Pacific</a>
                 ,   10°30'N, 131°20'W (EP-1), 21 August 2009: Six females (NIBRIV0000882758-882763) and four males (NIBRIV0000882764-882767) dissected on several slides, respectively. All dissected specimens, one undissected female (NIBRIV0000882768) and one undissected male (NIBRIV0000882769) on respective H-S slide, and five undissected females and two undissected males in alcohol vial (NIBRIV0000882770) were deposited in the NIBR. (3) Korea  
                <a title="Search Plazi for locations around (long -131.33333/lat 10.5)" href="https://tb.plazi.org/GgServer/search?materialsCitation.longitude=-131.33333&amp;materialsCitation.latitude=10.5">Strait</a>
                 ,   33°44'50.50"N, 128°15'39.02"E (KS), 7 October 2008: Three females (NIBRIV0000882771-882773) and one male dissected (NIBRIV0000882774) on H-S slide, respectively.  
                <a title="Search Plazi for locations around (long 128.26083/lat 33.74736)" href="https://tb.plazi.org/GgServer/search?materialsCitation.longitude=128.26083&amp;materialsCitation.latitude=33.74736">All</a>
                 dissected specimens and two undissected females and two undissected males in alcohol vial (NIBRIV0000882775) were deposited in the NIBR  . 
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            <p>
                 2. Elongate form. (1)   
                <a title="Search Plazi for locations around (long -131.33333/lat 10.5)" href="https://tb.plazi.org/GgServer/search?materialsCitation.longitude=-131.33333&amp;materialsCitation.latitude=10.5">Northwestern Pacific</a>
                 , 13°23'46.44"N, 143°55'0.60"E (WP-1), 27 March 2016: One female (NIBRIV0000882776) dissected on two slides. This specimen was deposited in NIBR. (2) Northeastern Pacific, 10°30'N, 131°20'W (EP-1), 21 August 2009: Three females (NIBRIV0000882777-882779) dissected on one slide or three slides, respectively. Two females (aberrant) (NIBRIV0000882780) dissected on H-S slide. The morphometric data provided in Tables 3 and 4 included only four specimens (three normal females and one aberrant female). All dissected specimens except for one specimen of aberrant female and one undissected aberrant female (in alcohol, NIBRIV0000882781) were deposited in the NIBR  . 
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            <p>Description.</p>
            <p> Female (robust form, Figs 2 - 4, 6, 7D, E, 16A-D, Tables 3, 4). Body length (in lateral view, telescoping of somites not considered) range 318-373  µm in Pacific specimens (Table 3), showing a wider size range than in the Red Sea (330-340  µm ,  Böttger-Schnack 2003: 193). </p>
            <p> Prosome 1.9  × length of urosome, excluding caudal rami, 1.6  × urosome length, including caudal rami (Fig. 2B), calculated by not correcting for the telescoping of somites. Variation of prosome to urosome length (including CR) ratio 1.5-1.7 in Pacific specimens (Table 3). The respective values provided for Red Sea specimens are not comparable as they were based on length data corrected for the telescoping of somites. When calculating the body proportions of the female from  Böttger-Schnack’s fig. 2A by not correcting for the telescoping of somites, the respective ratio of prosome to urosome length (incl. CR) would account to 1.5, which is within the range of values for Pacific specimens. </p>
            <p>P5-bearing somite with paired row of midventral spinous processes (Fig. 2E), variable in number, generally two or three processes, difference per body side may appear as in Fig. 2E: four (right) and two (left). No such variation was mentioned for the Red Sea specimens.</p>
            <p> Posterior margin of genital double-somite and postgenital somites with undulate hyaline frill (Fig. 2C, E), as typical for  Spinoncaea species, shown in detail in Fig. 16D. </p>
            <p> Genital double-somite (Figs 2C, D, E, 16D) 2.0  × as long as maximum width in specimen figured (measured in dorsal aspect) and ~ 1.5  × as long as postgenital somites combined; variation in length to width ratio 1.6-2.0 in Pacific specimens (Table 3), surface ornamentation and pore pattern as figured (Figs 2E, 16D). </p>
            <p>Anal somite approximately as wide as long, with insignificant variation in length to width ratio (Table 3), ornamentation as figured (Fig. 2C, E).</p>
            <p> Caudal ramus (Fig. 2A, C, G) with length to width ratio 1.9-2.2 measured along inner margin and 2.4-2.9 measured along outer margin (Table 3). Caudal seta II with a single long spinule (as in male, e.g., Fig. 16E), which is difficult to discern, and which was not reported for Red Sea specimens, and seta IV with ornamentation being unipinnate, while it is bipinnate in Red Sea specimens. Variation in length ratios among setae II, III, and IV as given in Table 3, denoting a smaller ratio for seta III:II (1.3-1.9) than in the Red Sea (2.2;  Böttger-Schnack 2003: fig. 2F). </p>
            <p> Antennule 6-segmented (Fig. 3A) with armature formula: 1-[3], 2-[8], 3-[5], 4-[2+ae], 5-[2 (ae not discernible)], 6-[5+(1+ae)], typical for  Spinoncaea species. </p>
            <p> Antenna 3-segmented, armature as for Red Sea specimens, including the absence of seta IV on the lateral armature of the distal endopod segment (Fig. 3B, setae I-III indicated). Distal endopod segment reflexed (Fig. 3B), 3.0-3.9  × longer than wide (Table 3), somewhat longer than reported for Red Sea specimens (ca 3:1; discussed under  “Remarks” ). Ornamentation of elements differing slightly from Red Sea specimens in (1) the coxobasis with a long seta at inner distal corner is ornamented with long spinules unilaterally along entire length, including a single very long spinule at distal part, but only a short row of small spinules at anterior half (Fig. 3B), while in specimens from the Red Sea this seta is ornamented with strong spinules bilaterally and lacking a single long spinule (  Böttger-Schnack 2003: fig. 3A), and on (2) the proximal endopod segment is lacking single strong spine on expanded outer margin in specimen figured (Fig. 3B), but is present in specimen from Korea Strait (Fig. 6A), as specified for Red Sea specimens. </p>
            <p>Labrum (Figs 3G, H, 16A) showing variable ornamentation on anterior surface, paired row of long setules in specimen figured (Fig. 3G, indicated by white arrow in Fig. 16A) as specified for Red Sea specimens, additional row of setules indicated in specimen from Korea Strait (Fig. 6C).</p>
            <p> Mandible (Fig. 3C) gnathobase with five elements, with dorsal element D shortest and inserting near base of seta E, as typical for  S. ivlevi (cf.  Böttger-Schnack 2003: 191) difficult to discern in some specimens from the Pacific. </p>
            <p> Maxillule (Figs 3D, 16B) with six elements [innermost element on outer lobe absent, as typical for  Spinoncaea species]; ornamentation of middle and innermost element on inner lobe as well as of element next to innermost on outer lobe (Fig. 16B) slightly modified as compared to Red Sea specimens. </p>
            <p>Maxilla (Fig. 3E) with additional ornamentation on syncoxa showing rows of short spinules along outer margin and long spinules along inner margin (arrowed in Fig. 3E), not reported earlier for Red Sea specimens.</p>
            <p> Maxilliped (Fig. 3F, syncoxa missing) with basis ornamented with fringe of short spatulated spinules between distal seta and articulation with endopod, as illustrated for Red Sea specimens (  Böttger-Schnack 2003: fig. 3G, but erroneously described as  “… between proximal seta and articulation with endopod;.." in text on p 200). </p>
            <p>Swimming legs 1-4 (Fig. 4A-D) with armature formula shown in Table 2. Intercoxal sclerite of P1 ornamented with paired long, fine setules (Figs 4a, 16C), which were not discernible in some specimens. Outer seta on basis of P1 slightly shorter than in Red Sea specimens and naked. Anterior surrounding of bases of spines on exopodal and endopodal segments (= small spinules) not discerned in Pacific specimens.</p>
            <p>Exopods with general characteristics as for Red Sea specimens, including a reduced length of spine on middle segment (= exp-2) of P2 and P3 (Fig. 4B, C) and of proximal spine on distal segment (= exp-3) of P2 (Fig. 4B); variability of proportional spine lengths, however, indicates that extent of size reduction of spine on exp-2 differs between legs: most obvious on P2, less obvious on P3 and insignificant on P4 (Table 4). Distal spine on P1 slightly longer, on P2-P4 shorter than distal exopod segment, variability of respective length ratios (Table 4) indicating that the respective size difference is less obvious in P2 as compared to P3 and P4.</p>
            <p> Endopods with length ranges of outer subdistal spine and outer distal spine relative to distal spine given in Table 4 generally similar to Red Sea specimens (  Böttger-Schnack 2003: fig. 4A-D). </p>
            <p>P5 (Fig. 2C, D, F) with length to width ratio of exopod segment 1.6, as for Red Sea specimens.</p>
            <p>P6 (Fig. 2C) represented by operculum closing off each genital aperture; possibly armed with a short spinule, which is difficult to discern in Pacific specimens.</p>
            <p> Female (elongate form, Fig. 7A - C, Tables 3, 4). Body length range 305-345  μm , based on five specimens from tropical northeastern and northwestern Pacific, not significantly different from robust form (Table 3). </p>
            <p> Prosome 1.3-1.4  × length of the urosome (incl. CR), smaller than in the robust form (1.5-1.7, Table 3). </p>
            <p>Genital double-somite with shape slightly different from robust form, degree of tapering being stronger (Fig. 7A) than in robust form (Fig. 2C). Length to width ratio of the genital double-somite (1.9-2.2) slightly larger than in robust form (1.6-2.0), but values overlap (Table 3).</p>
            <p>Anal somite with length to width ratio larger in elongate form (1.2-1.4) than in robust form (1.0-1.1) (Table 3); longer than CR (measured along outer margin) while in the robust form the anal somite is shorter than the CR (cf. Fig. 2A, C, E).</p>
            <p>Caudal ramus with ranges in length to width ratio overlapping between the two female form variants (Table 3).</p>
            <p> Antennule (not figured) 6-segmented. Armature formula as for  S. ivlevi robust form. </p>
            <p> Antenna (not figured) 3-segmented, armature as for  S. ivlevi robust form. Distal endopod segment with variation of length to width (Table 3). </p>
            <p>Mandible, maxillule, maxilliped (not figured) similar to those of the robust form.</p>
            <p>Swimming legs variable in proportional lengths of endopodal and exopodal spines on P2-P4 as given in Table 4, showing similar ranges of variation among both forms of the species (cf. Table 4).</p>
            <p>* = data from the left/right legs of one specimen; if there is only one datum, it means that the values are the same or only one side was measured.</p>
            <p> Male (Figs 5, 16E, Tables 3, 4). Body length range 298-331  µm in Pacific specimens (Table 3). Sexual dimorphism in antennule, maxilliped, P6, and in genital segmentation, slight modification in setal length of P5. </p>
            <p>P5-bearing somite with paired row of midventral spinous processes (Fig. 5D), variable in number, generally two or three processes.</p>
            <p>Caudal rami (Fig. 5A, D, F) with length to width ratio 1.7-2.0 measured along inner margin and 2.3-2.7 measured along outer margin (Table 3). Caudal setae with variations in proportional lengths of caudal setae III:II and setae IV:III as given in Table 3, similar to female. CR seta II ornamented with single long spinule in some specimens (Fig. 16E), not noted for specimens from Red Sea.</p>
            <p> Dorsal surface of genital somite ornamented with pattern of minute denticles or spinules (Fig. 5D), which are less distinct than in Red Sea specimens (  Böttger-Schnack 2003: fig. 5D), ventral surface with spinule pattern on anterior part (Fig. 5F) not observed in Red Sea specimens (  Böttger-Schnack 2003: fig. 5E). Surface of genital flaps covered with several rows of strong denticles or spinules (Fig. 5E, F), few denticles also observed on inner distal part (Fig. 5D) not observed in Red Sea specimens (  Böttger-Schnack 2003: fig. 5D). </p>
            <p>Antennule (Fig. 5G) 4-segmented, armature formula: 1-[3], 2-[8], 3-[4], 4-[9+2ae+(1+ae)], aesthetascs very small and slender, segment 4 with small middle aesthetasc close to seta present, which is not discernible in the female. Ornamentation as figured.</p>
            <p>Antenna (not figured) with variation in length to width ratio of distal endopod segment similar to female (Table 3).</p>
            <p>Maxilliped (Fig. 5B, C) 3-segmented, comprising syncoxa, basis and 1-segmented endopod, armature and ornamentation as figured. Basis with only one long seta within longitudinal cleft, corresponding to distal seta in female, proximal seta absent (Fig. 5C). Endopod represented by long curved claw, tip of claw without hyaline apex.</p>
            <p>Swimming legs 1-4 with armature and ornamentation as in female. Variability in length ratios of outer spine on exp-1 relative to outer spines on exp-2 and exp-3 of P2-P4, and length ratios of outer subdistal spine and outer distal spine relative to distal spine on enp-3 of P2-P4 given in Table 4, not significantly different from female.</p>
            <p>P5 (Fig. 5E, F) exopod with general shape and armature as in female; exopodal seta and outer basal seta somewhat shorter than in female.</p>
            <p>P6 (Fig. 5F) represented by posterolateral flap closing off genital aperture on either side, ornamented as described above, posterolateral corners well discernible in dorsal aspect (Fig. 5A, D).</p>
            <p>Remarks.</p>
            <p> Böttger-Schnack (2003) provided a comprehensive redescription of  S. ivlevi from the Red Sea and various other regions and included a detailed discussion of  Shmeleva’s descriptions of the species in 1966 (original account) and in 1969 and of that record by Malt (1982). Therefore, these papers are not further discussed in the present paper and the data presented by  Böttger-Schnack (2003) were mainly used as a reference for comparison with the Pacific specimens. However, one detail of  Shmeleva’s original illustration is noteworthy, as the shape of the distal endopod segment on the antenna is much more slender in both sexes (Shmeleva 1966: fig. 1.4; 1969: figs 3d, 4c) than figured in  Böttger-Schnack’s account for the robust form of the female (2003: fig. 3A). In specimens of both female form variants from the Pacific the distal endopod segment of the antenna appears to be relatively longer and more slender than figured for the Red Sea specimens, showing a range of variation in length to width ratio of 3.0-3.9 in Pacific (cf. Table 3), while this ratio is described as "about three times longer than wide" in the Red Sea (  Böttger-Schnack 2003: 198). As the figure of the specimen from the Korea Strait (Fig. 6A) also shows a somewhat stronger reflexed orientation of the distal segment compared to the specimen from the equatorial Pacific (Fig. 3B), the length to width ratio may be underestimated. But the respective figure (Fig. 6A) does not give clear evidence about its actual length to width ratio, because the strongly reflexed orientation of the distal antennary segment makes it difficult to measure it from this figure. </p>
            <p> Some other differences between our study and  Böttger-Schnack’s redescription were detected in the presence of few long fine setules on the intercoxal sclerite of P1 in both sexes (Figs 4a, 16C), and the distinct ornamentation of the ventral anterior surface of the genital somite in the male (Fig. 5F). The first character mentioned has so far been found only in one other  Spinoncaea species,  S. tenuis (cf.  Böttger-Schnack 2003: fig. 14A), and is recorded for  S. ivlevi in the present account for the first time, but seemed to be variable, being present in most but not all specimens examined from the three locations in the Pacific (e.g., eight of eleven females and three of four males in the northwestern Pacific). </p>
            <p> Additional or different ornamentation details found in the Pacific specimens of  S. ivlevi , not mentioned and/or not figured by  Böttger-Schnack (2003) included mainly details on the surface of elements such as on the maxilla (syncoxa with additional spinule pattern, Fig. 3E), or small details on setae, such as on the inner seta on the coxobasis of the antenna (Figs 3B, 6A) and on the middle element on the outer lobe of the maxillule (Figs 3D, 16B). These delicate ornamentation details can be discerned much better under a scanning electronic microscope as used in the present study than under a light microscope. </p>
            <p> Despite the ornamentation differences between the redescription (  Böttger-Schnack 2003) and the present account, specimens from the equatorial and temperate Pacific Ocean were regarded as conspecific with  S. ivlevi because our specimens showed basic morphological characters of  S. ivlevi , such as: </p>
            <p>the mandible showing the full set of 5 elements,</p>
            <p>the length to width ratio of the caudal ramus,</p>
            <p>the proportional lengths of caudal setae,</p>
            <p>the shape of caudal seta IV, which is setiform and not dilated as in S. tenuis,</p>
            <p>the shape and ornamentation of the female genital double-somite, and</p>
            <p>the paired row of long setules on the anterior surface of the labrum.</p>
            <p>In addition, the results of the molecular genetic analysis, which are presented, also supports this opinion, and is briefly discussed below.</p>
            <p> Similar to the report from the Red Sea (  Böttger-Schnack 2003), females of  S. ivlevi exhibited two form variants in the equatorial northeastern and northwestern Pacific. Taking into consideration the variability of morphological characters of the two variants as examined in the present account (Tables 3, 4), the following differences between the two female forms reported by  Böttger-Schnack (2003: 204) could be confirmed for specimens from the Pacific: (1) the length to width ratio of the anal somite, which is larger in the elongate form (1.2-1.4) than in robust form (1.0-1.1), (2) the length ratio of prosome to urosome which is smaller in the elongate form (1.3-1.4) than in the robust form (1.5-1.7), and (3) the shape of the genital double-somite, which shows a stronger degree of tapering in the elongate form (Fig. 7A) as compared to the robust form (Fig. 2C). On the other hand, the difference between the two forms in the length to width ratio of the genital double-somite indicated in  Böttger-Schnack´s study (2003: 204) was not confirmed, because the respective values in the Pacific specimens overlapped. (Table 3). Also, the variability of the length to width ratio of the caudal ramus is similar for both variants, and the range of values of proportional spine lengths of endopodal and exopodal spines on P2-P4 overlap between the two forms, including the values of these spines calculated from the robust form in  Böttger-Schnack (2003: fig. 4B-D). The P5-bearing somite of the elongate form from the equatorial Pacific exhibits one pair of weakly developed ventrolateral lobes (Fig. 7B, C), which is not mentioned in the descriptive text of  Böttger-Schnack (2003), but was shown in her fig. 6b. In the robust form, these lobes were not observed in specimens from the two locations in the equatorial Pacific areas (cf. Fig. 2E), but were weakly pronounced in specimens from the Korea Strait (Fig. 4D, arrowed). </p>
            <p> In the Pacific, individual variation between specimens was found e.g., in the number of midventral spinous processes on the P5-bearing somite, either two or three in both sexes, and some individuals also had different numbers between left and right side (Fig. 2E). It is common that there is no fringe of long setules on outer margin of proximal endopod segment of P4 in  S. ivlevi , but in some individuals this fringe was present (not figured). Furthermore, individual variation in ornamentation appeared (1) in the caudal seta II in some individuals, ornamented with a single long spinule in both sexes, (2) in the ornamentation on the dorsal anterior surface of the genital double-somite of females (cf. Fig. 2C), not observed in all specimens. One of the robust females from the Korea Strait (Fig. 6A-D) showed intraspecific variation in the outer distal part of the first endopod segment of the antenna with broad and more numerous spinules (arrowed in Fig. 6a), in additional setules on the anterior surface of the labrum (Fig. 6C), in one of the spinules on the inner margin of the syncoxa of the maxilla being relatively long (arrowed in Fig. 6B), and in the weak development of the ventrolateral lobes on the P5-bearing somite (Fig. 6D). </p>
            <p> A number of morphological aberrations found in some specimens of  S. ivlevi were summarized in Table 5. In the northwestern Pacific Ocean, three out of eleven robust female form variants and one out of four males showed abnormalities. Two aberrant specimens were ornamented with a patch of long setules on the anterior part of the cephalosome (Fig. 7D, E) and the other one robust female was ornamented with a very long setule on the dorsal anterior surface of the genital double-somite. In the northeastern Pacific Ocean, three out of six elongate females showed a pair of extremely long setules on both sides of the P4-bearing somite in ventral view (e.g., Fig. 7B), and one of them had also two extremely long setules on the ventral anterior surface of the genital double-somite (Fig. 7B). In the Korea strait, one robust female showed an atypical spine count on the right leg of P2, with only two outer spines on P2exp-3 [typical for the spine count on P2exp-3 of  S. humesi ] and with an inner setal count of four setae instead of five setae, while the armature on the right leg was normal. One male from the Korea strait showed imperfect and/or flawed segmentation of endopod segments on the antenna, and the distal part of abnormal distal segment has aberrant four setae. </p>
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	https://treatment.plazi.org/id/E63B3C5F7FA2574CA9783806118B21F6	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Cho, Kyuhee;Park, Chailinn;Boettger-Schnack, Ruth	Cho, Kyuhee, Park, Chailinn, Boettger-Schnack, Ruth (2021): Taxonomy of three species of the genus Spinoncaea (Copepoda, Oncaeidae) in the North Pacific Ocean with focus on morphological variability. ZooKeys 1043: 147-191, DOI: http://dx.doi.org/10.3897/zookeys.1043.64438, URL: http://dx.doi.org/10.3897/zookeys.1043.64438
C353F0A5613C56FD8BC1164C838FCF7C.text	C353F0A5613C56FD8BC1164C838FCF7C.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Spinoncaea tenuis Boettger-Schnack 2003	<html xmlns:mods="http://www.loc.gov/mods/v3">
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            <p> 
Spinoncaea tenuis 
Boettger-Schnack
, 2003
 Figs 8, 9, 10, 11 </p>
            <p> Spinoncaea tenuis Böttger-Schnack , 2003: 215-225, figs 12-16 (Red Sea, Mediterranean, Arabian Sea, Pacific Ocean). </p>
            <p>Material examined.</p>
            <p>
                 (1)   
                <a title="Search Plazi for locations around (long 128.26083/lat 33.74736)" href="https://tb.plazi.org/GgServer/search?materialsCitation.longitude=128.26083&amp;materialsCitation.latitude=33.74736">Northeastern Pacific</a>
                 (a) 10°30'N, 131°20'W (EP-1), 21 August 2009: One female (habitus of  S. tenuis female in Fig. 8A, B) and one male (habitus of  S. tenuis male in Fig. 11A) undissected on H-S slide, respectively. Five females and two males dissected on several slides, respectively. Three females dissected on H-S slide, respectively. Six dissected females (NIBRIV0000882784-882789) and one dissected male (NIBRIV0000882790) and one undissected female (NIBRIV0000882782) and one undissected male (NIBRIV0000882783) on respective H-S slide were deposited in the NIBR. (b) 9°52'1.38"N, 131°45'38.28"W (EP-2), 19 March 2019. Two undissected females and two undissected males in alcohol vial (NIBRIV0000882791) were deposited in the NIBR. (2) Northwestern Pacific, 13°20'3.42"N, 144°20'2.7"E (WP-2), 4 April 2016. One undissected male in alcohol vial (NIBRIV0000882792) was deposited in the NIBR. (3) Korea Strait, 33°44'50.50"N, 128°15'39.02"E (KS), 7 October 2008: One female (NIBRIV0000882793) and one male (NIBRIV0000882794) dissected on H-S slide, respectively. All dissected specimens and one undissected female (in alcohol, NIBRIV0000882795) were deposited in the NIBR  . 
            </p>
            <p>Description.</p>
            <p> Female (Figs 8 - 10, Tables 3, 4). Body length in lateral view (telescoping of somites not considered) (Fig. 8B) 320-355  µm in Pacific specimens (Table 3), somewhat larger than in the Red Sea (280-300  µm ,  Böttger-Schnack 2003: 215). </p>
            <p> Prosome 1.7  × length of urosome, excluding caudal rami, 1.5  × urosome length including caudal rami in specimens figured (Fig. 8B), calculated by not correcting for the telescoping of somites. Variation of prosome to urosome length (including CR) 1.3-1.7 in Pacific specimens (Table 3), single value from Korea Strait smallest. The respective values provided for Red Sea specimens (1.5 incl. CR;  Böttger-Schnack 2003: fig. 12A, calculated by not correcting for telescoping of somites) are within the range of values from the Pacific. </p>
            <p> P5-bearing somite with paired midventral spinous processes variable in number (two or three processes) and one pair of ventrolateral lobate processes (arrowed in Fig. 8D, E). Variation in number of midventral spinous processes was not mentioned for Red Sea specimens and ventrolateral lobes were not described, but are vaguely discernible from  Böttger-Schnack (2003: fig. 12I). </p>
            <p> Genital double-somite (Fig. 8C, D, E) 2.1  × as long as maximum width in specimen figured (measured in dorsal aspect) and ~ 2.1  × as long as postgenital somites combined; variation in length to width ratio 1.8-2.3 in Pacific specimens (Table 3), respective values from Red Sea fall within this range. Largest width measured at 2/5 the distance between anterior and posterior margin, similar to Red Sea specimens, where it is "about halfway". Ventral surface with few rows of minute spinules in some specimens (Fig. 8E), difficult to discern; this ornamentation was not mentioned for Red Sea specimens. Paired genital apertures located dorsally at about same position as in Red Sea specimens, armature difficult to discern. Weakly pronounced undulate hyaline frill on posterior margin of genital double-somite and postgenital somites and pore pattern as figured (Fig. 8D, E). </p>
            <p>Anal somite (Fig. 8C) length to width ratio ranging between 1.1-1.3 (Table 3), ornamentation as figured (Fig. 8C, D, E).</p>
            <p> Caudal ramus (Fig. 8A, C) length to width ratio 1.8-2.5 measured along inner margin and 2.3-3.0 measured along outer margin (Table 3). Caudal seta III ornamented with few minute spinules along medial margin (Fig. 8C), not observed in Red Sea specimens. Length ratio between seta IV and III 1.4-2.3 (Table 3), seta IV unipinnate, not bipinnate as in Red Sea specimens (  Böttger-Schnack 2003: fig. 12C). </p>
            <p> Antennule 6-segmented (Fig. 9A). Armature formula and ornamentation as for  S. ivlevi . </p>
            <p> Antenna 3-segmented, armature and ornamentation as figured (Fig. 9B). Distal endopod segment with length to width ratio 3.3-4.1 in Pacific specimens (Table 3), seta II longer than seta I (as illustrated for Red Sea specimens,  Böttger-Schnack 2003: fig. 13A, but erroneously described as being "shorter than seta I" in text on p. 217). </p>
            <p> Labrum with ornamentation as figured (Fig. 9G, H). including difference to  S. ivlevi in (1) size of three marginal teeth along distal (ventral) margin on each lobe (arrowed in Fig. 9G) being somewhat smaller than in  S. ivlevi , and (2) presence of two paired rows of long setules on anterior surface (Fig. 9G), not only a single paired row as in  S. ivlevi . </p>
            <p> Mandible with armature and ornamentation as figured. (Fig. 9C), small element D on gnathobase absent, as typical for  S. tenuis (cf.  Böttger-Schnack 2003: 218, fig. 13D). </p>
            <p> Maxillule (Fig. 9D) similar to  S. ivlevi , except for middle element on inner lobe naked. </p>
            <p>Maxilla (Fig. 9E) with additional ornamentation on surface of syncoxa (arrowed in Fig. 9E), not reported earlier for Red Sea specimens.</p>
            <p>Maxilliped as figured (Fig. 9F), surface of syncoxa ornamented with few spinules (arrowed in Fig. 9F), which was not recorded for Red Sea specimens.</p>
            <p> Swimming legs 1-4 (Fig. 10A-D), with armature as in  S. ivlevi (Table 2). Intercoxal sclerites of P1 ornamented with paired long, fine setules (but only one paired setule shown in Fig. 10A), which are difficult to discern. Ornamentation on inner portion of basis in P1-P3 as figured (Fig. 10A-C). </p>
            <p> Exopods with variability of proportional spine lengths given in Table 4, respective values from the Red Sea fall within this range (  Böttger-Schnack 2003: fig. 14A-D), except for the proportional lengths of outer spines on P3, which are larger in Pacific specimens than in the Red Sea specimens. Distal spine slightly longer than (P1) or almost equal in length (P2-P4) to distal exopod segment, similar to Red Sea specimens (  Böttger-Schnack 2003: fig. 14A-D). </p>
            <p> Endopods. Length ranges of outer subdistal spine and outer distal spine relative to distal spine on P2-P4enp-3 as given in Table 4 generally similar to Red Sea specimens (  Böttger-Schnack 2003: fig. 14A-D). </p>
            <p> P5 (Fig. 8C, D, F) exopod 1.7  × longer than wide, armature and ornamentation as figured. </p>
            <p>P6 (Fig. 8C) as figured, possibly armed with a short spinule, which is difficult to discern.</p>
            <p> Male (Fig. 11, Tables 3, 4). Body length 292-325  µm (Table 3). Sexual dimorphism in antennule, maxilliped, P6, and in genital segmentation, slight modification in setal length of P5. Pore pattern on prosome not discerned. </p>
            <p>P5-bearing somite with paired row midventral spinous processes variable in number as in female and one pair of ventrolateral lobate processes (Fig. 11C).</p>
            <p>Caudal rami (Fig. 11A, B, C, G) with length to width ratio 1.9-2.4 measured along inner margin and 2.2-2.8 measured along outer margin (Table 3), ornamentation as figured (Fig. 11D). Caudal setae with proportional lengths as in female, variation in length ratios as given in Table 3.</p>
            <p> Antennule (Fig. 11E) 4-segmented, armature as for  S. ivlevi . </p>
            <p>Antenna (not figured) with variation in length to width ratio of distal endopod segment similar to female (Table 3).</p>
            <p>Maxilliped (Fig. 11D) 3-segmented, armature and ornamentation as figured.</p>
            <p>Swimming legs 1-4 with armature and ornamentation as in female. Variability in proportional spine lengths on rami given in Table 4, values of equatorial Pacific fall within the range of females, but proportional lengths of exopodal spines on P2 and P4 from Korea Strait larger than those of females.</p>
            <p>P5 (Fig. 11F) with exopodal seta and outer basal seta somewhat shorter than in female.</p>
            <p>P6 (Fig. 11C) with ornamentation pattern as figured.</p>
            <p>Remarks.</p>
            <p> Böttger-Schnack (2003) reported two variants of female  S. tenuis which differed in geographical distribution. The typical form appeared in the entire Red Sea and in the northern Arabian Sea, while the elongate form was found in the Mediterranean Sea and in the NW Pacific (Kuroshio Extension); specimens from the NE Pacific (Monterey), on the other hand, showed intermediate values between both forms. In the present study, females from the NE equatorial Pacific also displayed intermediate values in morphological characters between the two forms of  S. tenuis , which are as follows: (1) the length to width ratio of the genital double-somite has a wide range (1.8-2.3), including values of both form types; (2) the position of the genital apertures is at 2/5 of distance from the anterior margin as in the elongate form (from the Adriatic Sea); (3) the basal seta on P4 is more similar to the typical Red Sea form, reaching as far as the middle of the distal exopod segment, whereas this seta is much longer in the elongate form (from the Adriatic Sea), reaching beyond the tip of the distal spine on the exopod segment (cf.  Böttger-Schnack 2003: fig. 16C); (4) the outer basal seta on P5 reaching as far as 4/5 the distance from the anterior margin of the genital double-somite in our Pacific specimens, but extending almost beyond the posterior margin of the genital double-somite in the elongate form (from the Adriatic Sea), (5) the length to width ratio of the caudal ramus measured along inner or outer margin in our specimens (1.8-2.5 or 2.3-2.9  × , respectively) is larger than in the typical form from the Red Sea (1.9-2.0 or 2.1-2.3  × ) at least for ratio of the outer margin, and the range of values corresponds approximately to those of the elongate form from the Adriatic Sea (1.8-2.4 or 2.2-2.6  × ) and the NE Pacific (off Monterey, California) (2.1 or 2.4-2.7  × ) (  Böttger-Schnack 2003: table 8). </p>
            <p> In terms of ornamentation details, which are described for the typical form only, our Pacific specimens differed from the typical  S. tenuis mainly by some details such as: (1) (1a) on the syncoxa of the maxilla and (1b) on the proximal element of the maxilliped; (2) short spinule(s) on the inner margin of bases on P2 and P3; (3) ornamentation with few minute spinules along the medial margin of CR seta III; and (4) variable number of midventral spinous processes on the P5-bearing somite. </p>
            <p> Unlike the females, males of  S. tenuis could not clearly be classified into form types in  Böttger-Schnack’s account. When compared to the typical form from the Red Sea, specimens from the equatorial Pacific are similar in morphology, except for some minor differences including (1) the length to width ratio of the genital somite, which is longer than in our specimens (1.8-2.0  × ) than in the Red Sea specimens (1.7  × ), (2) the caudal rami (inner 1.9-2.2  × , outer 2.2-2.6  × ) were slightly longer than in the Red Sea specimens (inner 1.9  × , outer 2.3  × ), and (3) the length ratio of caudal setae VII and IV, respectively, with seta VII being 1.6-1.9  × longer than seta IV in the Pacific specimens, whereas seta VII is only 1.4  × the length of seta IV in the Red Sea specimens. Also, the number of paired midventral spinous processes on the P5-bearing somite differs, showing only two processes in the Pacific, as compared to three processes in the Red Sea specimens. However, as the male specimen from the Korea Strait also showed three paired processes (not figured), and differences among individuals of  S. tenuis females (two or three processes) were apparent, this ornamentation seems to be due to individual variation, and cannot be regarded as a regional difference. </p>
            <p> According to  Böttger-Schnack (2003), some slight morphological differences occurred between males of  S. tenuis from the Red Sea and the Adriatic Sea (e.g., the proportional lengths of the genital somite and the caudal rami), but the determination of an elongate male appeared to be ambiguous. In our case, the above mentioned two characters are intermediate between the typical form (from the Red Sea) and the elongate form (from the Adriatic Sea) and the range of these values could be perceived as a variation among individuals (cf. Table 3). However, the single male of  S. tenuis from the Korea Strait (not figured) seemed to be similar to the elongate form from the Adriatic Sea, as it differed from specimens from the equatorial Pacific specimens in the following characters (Table 3): (1) smaller body length: 292  μm ; (2) the genital somite being slightly longer than in the equatorial Pacific, with a length to width ratio of 2.0:1; (3) the length to width ratio of the caudal rami being greater/higher (inner 2.4  × , outer 2.8  × ) than in the equatorial Pacific (Table 3); (4) the anal somite slightly longer than in the equatorial Pacific, 1.2  × longer than wide; and (5) the outer basal seta on P5 reaching the posterior margin of the genital somite. In summary, the observed variation of features for  S. tenuis in the Pacific indicates that the previously described form types of this species are not clearly separated; however, distinct form types may occur due to regionally reduced ranges of variation in the morphological details described here. </p>
            <p> The female of  S. tenuis can easily be confused with the elongate form of female  S. ivlevi from the Pacific Ocean, due to the shape of the genital double-somite. However, as  Böttger-Schnack (2003) mentioned the distinction between  S. tenuis and  S. ivlevi elongate form from the equatorial Pacific are: (1) the number of elements on the mandible (four in  S. tenuis , but five in  S. ivlevi elongate form) and (2) the number of spinules patches on the anterior surface of the labrum (two pairs in  S. tenuis , but one pair in  S. ivlevi elongate form, generally). Further morphometric differences between females of the two species may be found in (3) the proportional lengths of caudal setae III: II, which is smaller in  S. tenuis (1.0-1.5  × ) as compared to  S. ivlevi elongate form (1.6-2.0  × ) and (4) the length ratio between the distal spine and distal exopod segment on P2-P4, with the distal spine being almost equal in length to the distal segment in  S. tenuis , whereas the spine is shorter than the segment in  S. ivlevi elongate form (esp. on P4) (Table 4). Further minor differences between the two species are found in the patterns of the ornamentation on the ventral surface of the genital double-somite, as the elongate form of  S. ivlevi (Fig. 7B) has a larger number of spinular rows than  S. tenuis (Fig. 8E) and the ornamentation on the inner margin of caudal ramus, which is absent in  S. tenuis , but is present in  S. ivlevi elongate form. </p>
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	https://treatment.plazi.org/id/C353F0A5613C56FD8BC1164C838FCF7C	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Cho, Kyuhee;Park, Chailinn;Boettger-Schnack, Ruth	Cho, Kyuhee, Park, Chailinn, Boettger-Schnack, Ruth (2021): Taxonomy of three species of the genus Spinoncaea (Copepoda, Oncaeidae) in the North Pacific Ocean with focus on morphological variability. ZooKeys 1043: 147-191, DOI: http://dx.doi.org/10.3897/zookeys.1043.64438, URL: http://dx.doi.org/10.3897/zookeys.1043.64438
