Review of amphipods of the family Pleustidae Buchholz, 1874 (Crustacea Amphipoda) from the coastal waters of Sakhalin Island (Far East of Russia). I. Subfamily Neopleustinae Bousfield & Hendrycks, 1994 Labay, Vjacheslav S. Zootaxa 2021 2021-05-20 4974 2 267 306 7PM5M Stebbing, 1906 Stebbing 1906 [538,875,330,357] Malacostraca Pleustidae Neopleustes Animalia Amphipoda 34 301 Arthropoda genus    1. Body segments with strong dorsal teeth (fig. 1a,b, d–i)....................................................... 2  - Body segments without strong dorsal teeth (fig. 1c).............................  Neopleustes carinatus Margulis, 1963   2. Pereon segments 1–6 without carination, pereon segment 7 with strong dorsal tooth posteriorly (fig. 1a,b).............. 3  - Pereon with a large number of dorsal teeth (fig. 1d–i)........................................................ 4   3. Pereonal & pleonal segments without aesthetascs dorsally (fig. 1a).............  Neopleustes boecki boecki( Hansen, 1887)  - Pereonal & pleonal segments with submedial and sublateral groups of plumose aesthetascs dorsally (fig. 1b)...................................................................................  Neopleustes boecki pacificas sp. nov.   4. Pereon segments 1–4 without carination, pereon segments 5–7 with strong dorsal tooth posteriorly (fig. 1g,h,i).......... 5  - Pereon carinated posteriorly from segment 1 to segment 7 (fig. 1d,e,f)........................................... 7   5. Lower margin of coxal plate 1 rounded, without central ventral angle (fig. 4g).....  Neopleustes kussakini( Budnikova, 1995)  - Lower margin of coxal plate 1 with central ventral angle (fig. 4h,i).............................................. 6   6. Head, pereonal & pleonal segments without setae dorsally, lower margin of coxal plate 1 with acute central ventral angle (figs. 1h, 4h).......................................................  Neopleustes pulchellus pulchellus(Krøyer, 1846)  - Head, pereonal & pleonal segments with submedial and sublateral long pappose single setae dorsally, lower margin of coxal plate 1 with subquadrate central ventral angle (figs. 1i, 4i)...................  Neopleustes pulchellus asiaticuss sp. nov.   7. Body, pereon segments 1–3 weak carinations, and strongly carinated from segment 4 to segment 7 (fig. 1d).....................................................................  Neopleustes columbianus Hendrycks & Bousfield, 2004  - Body, pereon strongly carinated from segment 1 to segment 7 (fig. 1e,f).......................................... 8   8. Head with anterodorsal crest, lower margin of coxal plate 1 with acute central ventral angle (figs. 1e, 4e)................................................................................  Neopleustes euacanthoides Gurjanova, 1972  - Head without anterodorsal crest, lower margin of coxal plate 1 without acute central ventral angle (fig. 1f)...................................................................................  Neopleustes euacanthus(G. Sars, 1877)