Leucothoe amamiensis White & Reimer 2012

Head. Anterior margin rounded, anterodistal margin evenly rounded; ventral cephalic keel anterior margin excavate, anteroventral margin quadrate with a simple cusp, ventral margin oblique; eyes with more than 10 ommatidia, round. Antenna 1 0.3 × body length, flagellum 8–articulate, peduncle article 1 width less than 2 × article 2, accessory flagellum 1–articulate, aesthetascs present. Antenna 2 0.3 × body length, slightly shorter than antenna 1, flagellum 3–articulate. Mandibular palp ratio of articles 1–3 1.0: 3.5: 1.5, article 2 with 17 setae, article 3 with 2 distal setae, incisors strongly dentate; left mandible with 14 raker spines, lacinia mobilis large, strongly toothed; right mandible with 15 raker spines, lacinia mobilis small, weakly dentate, with 2 rows of dentition. Upper lip asymmetrically lobate, anterior margin setose. Lower lip inner lobes fused, bare; outer lobes with moderate gape, anterior margins setose. Maxilla 1 palp 2–articulate with 3 distal slender setae; outer plate with 7 distal robust setae and 3 distal slender setae. Maxilla 2 inner plate with 2 robust and 7 slender distal setae, short row of facial setae; outer plate with 11 distal marginal setae, facial setae present. Maxilliped inner plates distal margin with v-shaped indentation, with short robust setae; outer plate inner margin smooth, reaching 0.3 × palp article 1, with simple and setulate-serrate marginal setae, facial setae present; palp article 4 subequal in length with article 3, distally acute. Pereon. Coxae 1–4 relative widths 1.0: 1.0: 0.7: 1.4. Gnathopod 1 coxa smooth, with tiny marginal setae, anterodistal margin produced, subquadrate, posterior margin excavate, medial and lateral facial setae present; basis distally expanded, anterior margin with 18 setae, posterior margin bare; ischium with 1 posterodistal seta; carpus linear, length 9.1 × width, proximal margin smooth, distal margin with 3 short setae; propodus straight, palm dentate with 6 proximal setae; dactylus smooth, reaching 0.3 × propodus length. Gnathopod 2 coxa longer than broad, subequal in length with coxa 3, smooth, with tiny marginal setae, anterodistally rounded, distal margin straight, posterior margin straight, lateral facial setae present; basis distally expanded with 3 small anterior tubercles, anterior margin with 19 short and medium setae, posterior margin with 2 short setae; ischium with posterior, distal, and posterodistal setae; carpus 0.3 × propodus length, curved, with large subdistal tooth, anterior margin smooth; propodus with 1 mediofacial setal row displaced to palm, reaching 0.8 × propodus length, with 1 row of submarginal setae, posterior margin smooth, palm convex with 3 small and 1 major tubercle, indentation near distal end of dactylus; dactylus curved, proximal margin smooth with 1 seta, anterior margin distally subacute, reaching 0.6 × propodus length. Pereopod 3 coxa length 1.8 × width, anterodistal corner overriding distal face of coxa 2, extending below it, smooth, with tiny marginal setae, anterior margin straight, distal margin oblique, posterior margin straight, lateral facial setae present. Pereopod 4 coxa smooth, with tiny marginal setae, anterior margin tapered, distal margin produced, posterior margin excavate, lateral facial setae present. Pereopods 5–7 coxae facial setae present; bases width length ratios 1: 1.4, 1: 1.3, 1: 1.3, posterior margins smooth, setose. Pleon. Epimeron 1 with tuft of anteroventral setae, epimera 2–3 with ventral setae; epimeron 3 posteroventral corner subquadrate, produced. Uropods 1–3 relative lengths 1.0: 0.9: 1.1. Uropod 1 peduncle and outer ramus subequal in length with inner ramus; inner ramus with 6 robust setae; outer ramus with 2 robust setae. Uropod 2 peduncle 0.8 × inner ramus length; outer ramus 0.7 × inner ramus length; inner ramus with 5 robust setae; outer ramus with 3 robust setae. Uropod 3 peduncle 1.1 × inner ramus length; outer ramus subequal in length with inner ramus; inner and outer rami each with 3 robust setae. Telson 2.7 × longer than wide, with plumose facial setae and simple marginal setae, apex truncate.

East China Sea: Amami–oshima Island, Kagoshima, Japan.