taxonID	type	description	language	source
7F486FC6B28B598E83A4C8C1DA2EF024.taxon	description	Figs 2, 3, 4, 5, 6, 7 New Korean name: so-mae-mul-yeop-sae-u	en	Ahn, Yong-Uk, Lee, Chi-Woo, Min, Gi-Sik (2022): A new species of Gammarus (Crustacea, Amphipoda, Gammaridae) from South Korea. ZooKeys 1117: 53-69, DOI: http://dx.doi.org/10.3897/zookeys.1117.89610, URL: http://dx.doi.org/10.3897/zookeys.1117.89610
7F486FC6B28B598E83A4C8C1DA2EF024.taxon	materials_examined	Material examined. Holotype: male, dissected on 14 slides (NNIBRIV 92290), 9.0 mm, Maejuk-ri (34 ° 37 ' 23 " N, 128 ° 32 ' 57.1 " E), Somaemuldo Island, Hansan-myeon, Tongyeong-si, Gyeongsangnam-do, South Korea, October 7, 2021, collected by Y. U. Ahn. Paratypes: male, dissected on 10 slides (NNIBRIV 92291), 8.4 mm; male, dissected on 10 slides (NNIBRIV 92292), 8.8 mm; male, dissected on 10 slides (NNIBRIV 92293), 8.2 mm; male, dissected on 11 slides (NNIBRIV 92294), 8.4 mm; male, dissected on 11 slides (NNIBRIV 92295), 8.9 mm; female, dissected on 10 slides (NNIBRIV 92296), 8.2 mm; female, dissected on 10 slides (NNIBRIV 92297), 7.8 mm; 11 males and 3 females in ethanol vials (NNIBRIV 92298 - NNIBRIV 92311); all other data same as holotype.	en	Ahn, Yong-Uk, Lee, Chi-Woo, Min, Gi-Sik (2022): A new species of Gammarus (Crustacea, Amphipoda, Gammaridae) from South Korea. ZooKeys 1117: 53-69, DOI: http://dx.doi.org/10.3897/zookeys.1117.89610, URL: http://dx.doi.org/10.3897/zookeys.1117.89610
7F486FC6B28B598E83A4C8C1DA2EF024.taxon	etymology	Etymology. The specific name somaemulensis is derived from the name of the type locality, Somaemuldo Island.	en	Ahn, Yong-Uk, Lee, Chi-Woo, Min, Gi-Sik (2022): A new species of Gammarus (Crustacea, Amphipoda, Gammaridae) from South Korea. ZooKeys 1117: 53-69, DOI: http://dx.doi.org/10.3897/zookeys.1117.89610, URL: http://dx.doi.org/10.3897/zookeys.1117.89610
7F486FC6B28B598E83A4C8C1DA2EF024.taxon	diagnosis	Diagnosis. Antenna 2 with four clusters of long setae on posterior margin of peduncular article 4, calceoli absent; pereopods 3 and 4 with long straight setae on posterior margins of merus and carpus; pereopods 6 and 7 without anteroproximal setae on basis; inner ramus of uropod 3 reaching approximately 0.8 x as long as outer ramus, outer ramus with plumose setae on both margins, terminal article of outer ramus shorter than adjacent spines.	en	Ahn, Yong-Uk, Lee, Chi-Woo, Min, Gi-Sik (2022): A new species of Gammarus (Crustacea, Amphipoda, Gammaridae) from South Korea. ZooKeys 1117: 53-69, DOI: http://dx.doi.org/10.3897/zookeys.1117.89610, URL: http://dx.doi.org/10.3897/zookeys.1117.89610
7F486FC6B28B598E83A4C8C1DA2EF024.taxon	description	Description of male. Head (Fig. 2): rostrum short; inferior antennal sinus deep; eyes reniform. Antenna 1 (Fig. 3 A): peduncular articles 1 - 3 in length ratio 1.0: 0.7: 0.4, bearing distal setae clusters on each peduncular article; main flagellum 33 - articulate, each article with short distal setae; accessory flagellum four-articulate, article 4 very short. Antenna 2 (Fig. 3 B): peduncular article 1 with three short setae distally; gland cone tapering distally; anterior, posterior and interior margins of peduncular article 4 with four, four and five clusters of setae, respectively, length of longest seta on posterior margin 1.6 x the width of peduncular article 4; peduncular article 5 slightly longer than article 4, anterior, posterior and interior margins with six clusters of setae, respectively, length of longest seta on posterior margin 2.3 x the width of peduncular article 4; flagellum 11 - articulate, calceoli absent. Upper lip (Fig. 3 C): rounded, ventral margin with numerous minute setae. Lower lip (Fig. 3 D): inner lobes absent, outer lobes broad. Mandible (Fig. 3 E, F): incisor of left mandible with five teeth; lacinia mobilis of left mandible with four teeth; molar triturative, bearing one plumose seta; palp three-articulate in length ratio 1.0: 3.1: 2.2, article 1 unarmed, article 2 with 19 marginal setae, article 3 bearing eight B-setae on inner surface, six A-setae on outer surface, 28 D-setae on posterior margin and five E-setae apically; right mandible incisor with four teeth; lacinia mobilis of right mandible bifurcate, with small teeth. Maxilla 1 (Fig. 3 G, H): inner plate with 17 plumose setae; outer plate with 11 serrated spines apically; palp two-articulate and asymmetrical, right palp shorter and stouter than left palp, article 2 of right palp with five stout spines, one slender spine and one seta apically; article 2 of left palp with five slender spines and eight setae apically. Maxilla 2 (Fig. 3 I): inner plate bearing 17 plumose setae in an oblique row; outer plate broader than inner plate; both plates with numerous long setae apically. Maxilliped (Fig. 3 J): inner plate bearing three stout spines apically; outer plate with a row of blade-like spines and two plumose setae; palp four-articulate, article 1 unarmed, inner margin of article 2 with numerous setae, article 3 curved, with numerous setae on posterior margin and a row of subapical setae, article 4 hooked, with three setae at hinge of unguis. Gnathopod 1 (Fig. 4 A, B): coxal plate with two setae on both anterodistal and posterodistal corners; basis with long setae on both anterior and posterior margins; length of carpus 1.4 x as long as width, 0.8 x as long as propodus, bearing two clusters of setae on anterior margin; propodus pyriform in shape, palm oblique, with one medial palmar spine and 11 spines on posterior margin; dactylus exceeding near half of propodus, outer margin with one seta. Gnathopod 2 (Fig. 4 C, D): coxal plate with three setae on anterodistal corner and one seta on posterodistal corner; basis similar to that of gnathopod 1; length of carpus 1.7 x as long as width, 0.8 x the length of propodus, with four clusters of setae on anterior margin; propodus subrectangular in shape, palm concave, with one medial palmar spine and four spines on posterodistal corner; dactylus curved beyond the palmar margin, bearing one seta on outer margin. Pereopod 3 (Fig. 4 E, J): coxal plate with two setae on anterodistal corner and one seta on posterodistal corner; basis with long setae on both anterior and posterior margins; merus bearing two spines accompanied by setae on anterior margin, eight clusters of long straight setae on posterior margin, the longest seta of them approximately 2.0 x as long as width of merus, anterodistal corner bearing one spine accompanied by setae; carpus with five clusters of long straight setae on posterior margin, one spine accompanied by setae on both anterodistal and posterodistal corners; propodus with three spines accompanied by clusters of setae on posterior margin, one spine on posterodistal corner; dactylus bearing one plumose seta on anterior margin, two setae at hinge of unguis. Pereopod 4 (Fig. 4 F): coxal plate with posterior excavation, bearing two setae on anterodistal corner and four setae on posterior margin; basis similar to that of pereopod 3; merus with one spine accompanied by setae on anterior margin, four clusters of long straight setae on posterior margin, the longest seta of them approximately 1.4 x as long as width of merus, anterodistal corner bearing one spine accompanied by setae; carpus with three clusters of long straight setae on posterior margin, one spine accompanied by setae on both anterodistal and posterodistal corners; propodus with three spines accompanied by clusters of setae on posterior margin; dactylus similar to that of pereopod 3. Pereopod 5 (Fig. 4 G-I): coxal plate bilobed, posterior lobe with three setae on posterior margin; basis with two anteroproximal setae and six small spines on anterior margin, anterodistal corner bearing two spines accompanied by setae, posterior margin with 11 short setae, posterodistal lobe developed; merus with five clusters of setae on anterior margin, one spine on posterior margin, one and two spines accompanied by setae on anterodistal and posterodistal corners, respectively; carpus with three clusters of setae and two spines on anterior margin, two spines accompanied by setae on posterior margin; propodus with four groups of spines accompanied by setae on anterior margin; dactylus bearing one plumose on posterior margin, two setae at hinge of unguis. Pereopod 6 (Fig. 5 A, B): coxal plate bilobed, posterior lobe with three setae on posterior margin; basis with five small spines on anterior margin and without anteroproximal setae, posterior margin with 14 short setae, posterodistal lobe not developed; merus with six clusters of setae and two spines on anterior margin, two spines on posterior margin, one and two spines accompanied by setae on anterodistal and posterodistal corners, respectively; carpus with three groups of spines accompanied by setae on anterior margin, two groups of spines accompanied by setae on posterior margin; propodus with four groups of spines accompanied by setae on anterior margin; dactylus similar to that of pereopod 5. Pereopod 7 (Fig. 5 C-E): coxal plate shallowly concave ventrally, four setae on posterior margin; anterior margin of basis with five small spines and without anteroproximal setae, posterior margin with 15 short setae, inner surface near posterodistal corner with four short setae, posterodistal lobe not developed; merus with five clusters of setae and two spine on anterior margin, one spine on posterior margin, two spines accompanied by setae on both anterodistal and posterodistal corners; carpus with three groups of spines accompanied by setae on anterior margin, one spine and one cluster of setae on posterior margin; propodus with four groups of spines accompanied by setae on anterior margin; dactylus similar to those of pereopods 5 and 6. Coxal gills present on gnathopod 2 and pereopods 3 - 7. Pleonites 1 - 3 (Fig. 5 K-M): posterodorsal margins of pleonites 1 - 3 with four, four and five setae, respectively. Epimeral plates 1 - 3 (Fig. 5 H-J): plate 1 with three long setae on anteroventral margin and four short setae on posterior margin; plate 2 with two spines on ventral margin and six short setae on posterior margin; plate 3 with three spines on ventral margin and four short setae on posterior margin. Pleopods (Fig. 5 F, G): peduncle with two retinacula accompanied by one seta; inner ramus slightly longer than outer ramus, both rami fringed with plumose setae. Urosomites 1 - 3 (Fig. 6 F-H): dorsally flat; urosomites 1 and 2 with one-one-one-one spines accompanied by setae on dorsal margins from left to right, respectively; urosomite 3 with two spines accompanied by setae on left and right sides each, and three setae on dorsal margin. Uropod 1 (Fig. 6 A): peduncle bearing two basofacial spines, two and three spines on inner and outer margins, respectively, with one spine on both inner and outer distal corners; inner ramus approximately 0.7 x the length of peduncle and almost the same length as outer ramus, with two and one spines on inner and outer margins, respectively; outer ramus with two and three spines on inner and outer margins, respectively; both rami with five distal spines. Uropod 2 (Fig. 6 B): peduncle with one spine on inner margin and two spines on outer margin, one spine on both inner and outer distal corners; inner ramus approximately 0.9 x the length of peduncle and 1.3 x as long as outer ramus, with two and one spines on inner and outer margins, respectively; outer ramus with two spines on outer margin; both rami with five distal spines. Uropod 3 (Fig. 6 C, D): peduncle with several spines and setae on distal margin; inner ramus approximately 2.0 x as long as peduncle, reaching 0.8 x the length of outer ramus, bearing one distal spine, both inner and outer margins with plumose and simple setae; outer ramus two-articulate, proximal article with three spines on outer margin, bearing three distal spines, both inner and outer margins with plumose and simple setae, terminal article shorter than adjacent spines. Telson (Fig. 6 E): cleft nearly to base, width 0.9 x as long as length, each lobe with one cluster of setae and two single setae on surface, bearing one distal spine accompanied by five setae. Descrption of female. General appearance similar to male. Observed sexual dimorphism as follows: Antenna 2 (Fig. 7 A): setae of peduncular articles 4 and 5 longer than those of male, the longest seta on article 4 posterior margin 1.9 x as long as width of article 4, the longest seta of article 5 posterior margin 2.9 x as long as width of article 5. Gnathopod 1 (Fig. 7 B, C): palm not as oblique as that of male, with six spines posterior margin, medial palmar spine absent; dactylus not exceeding half of propodus. Gnathopod 2 (Fig. 7 D, E): carpus more elongate than that of male, length 1.2 x as long as propodus; palm with two spines on posterodistal corner, medial palmar spine absent. Oostegites: present on gnathopod 2 (Fig. 6 D) and pereopods 3 - 5, with numerous marginal setae. Uropod 3 (Fig. 7 F): both rami shorter than those of male, inner ramus 1.3 x as long as peduncle length, and 0.7 x the length of outer ramus.	en	Ahn, Yong-Uk, Lee, Chi-Woo, Min, Gi-Sik (2022): A new species of Gammarus (Crustacea, Amphipoda, Gammaridae) from South Korea. ZooKeys 1117: 53-69, DOI: http://dx.doi.org/10.3897/zookeys.1117.89610, URL: http://dx.doi.org/10.3897/zookeys.1117.89610
