Leucothoe chiisainame White & Reimer 2012

Head. Anterior margin excavate, anterodistal margin rounded, distal margin straight; ventral cephalic keel anterior margin excavate, anteroventral margin produced, rounded, ventral margin convex; eyes present with more than 10 ommatidia, round, small. Antenna 1 0.3 × body length, flagellum 7–articulate, peduncle article 1 width less than 2 × article 2, accessory flagellum 1–articulate. Antenna 2 0.2 × body length, shorter than antenna 1, flagellum 4–articulate. Mandibular palp broken in dissection, incisors strongly dentate; left mandible with 9 raker spines, lacinia mobilis large, strongly toothed; right mandible with 11 raker spines, lacinia mobilis small with 2 rows of dentition. Upper lip asymmetrically lobate, anterior margin setose. Lower lip lost in dissection. Maxilla 1 palp 2-articulate with 3 distal setae; outer plate with 5 distal robust setae. Maxilla 2 inner plate with 3 rows of 2, 2, and 3 distal setae, with 3 proximal marginal setae; outer plate with 2 distal robust setae and 13 marginal setae. Maxilliped inner plates with wide v-shaped indentation distally, with short simple robust setae and long slender setae; outer plate inner margin smooth, reaching 0.5 × palp article 1, with simple 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: 0.8: 1.4. Gnathopod 1 coxa with tiny marginal setae, anterodistal margin produced, subquadrate, serrate, distal margin straight, posterior margin excavate, facial setae absent; basis distally expanded, anterior margin with 7 short and medium setae, posterior margin bare; ischium with 2 short posterior setae; carpus linear, distal length 10.4 × width, proximal margin dentate, distal margin with 4 setae; propodus straight, palm dentate with 5 distal setae; dactylus smooth, reaching 0.3 × propodus length. Gnathopod 2 coxa broader than long, slightly larger than coxa 3, smooth, with tiny marginal setae, anterior margin expanded, anterodistally rounded, distal and posterior margins rounded, facial setae absent; basis distally expanded, anterior margin with 5 short and medium setae, posterior margin with 2 short setae; ischium with anterodistal, distal, and posterodistal setae; carpus 0.4 × propodus length, curved, distally truncate, anterior margin dentate; propodus with 1 mediofacial setal row displaced past midline, reaching 0.7 × propodus length, with 1 row of submarginal setae, posterior margin smooth, palm convex with 3 major and many small tubercles; dactylus curved, proximal margin smooth, bare, anterior margin distally acute, reaching 0.4 × propodus length. Pereopod 3 coxa length 1.1 × width, anterodistal corner overriding distal face of coxa 2 and extending below it, smooth, with tiny marginal setae, anterior margin straight, distal margin oblique, posterior margin straight, facial setae absent. Pereopod 4 coxa smooth, with tiny marginal setae, anterior margin tapered, distal margin rounded, posterior margin excavate, facial setae absent. Pereopod 5–6 coxae facial setae present, pereopod 7 coxa facial setae absent. Pereopods 5–7 bases width length ratios 1: 1.2, 1: 1.2, 1: 1.2, posterior margins serrate, setose. Pleon. Epimeron 1 with 1 antero-ventral seta, epimera 2–3 with ventral setae; epimeron 3 posteroventral corner subquadrate, produced. Uropods 1–3 relative lengths 1.0: 0.7: 1.0. Uropod 1 peduncle and outer ramus subequal in length with inner ramus; inner ramus with 3 robust setae, outer ramus with 4 robust setae. Uropod 2 peduncle 0.8 × inner ramus length, outer ramus 0.6 × inner ramus length; inner ramus with 4 robust setae, outer ramus with 3 robust setae. Uropod 3 peduncle and outer ramus 0.9 × inner ramus length; inner ramus with 3 robust setae, outer ramus with 1 robust seta. Telson 2.4 × longer than wide, apex weakly tridentate.

East China Sea: Yakushima Island, Kagoshima, Japan.