биота российских вод японского моря - Materials of Alexey Shipunov

orded in the Sea of Japan for May and August-September. The number of embryosvaries between 17 and 68.7. Genus Hemiacanthomysis Fukuoka et Murano, 2002Type species: Acanthomysis dimorpha Ii, 1936.Carapace anteriorly produced to relatively short triangular rostral plate. Eyes welldeveloped, trapezoid, slightly depressed dorsoventrally. Labrum with comparativelylong anterior spiniform process. Antennal scale lanceolate, with rounded apex, setoseall along length of inner and outer margins; subapical suture present. Marsupium consistsof 2 pairs of well-developed oostegites. Tergites of free thoracic segments and ofall abdominal segments smooth, without transverse furrows or transverse rows ofspines or setae. First to third and fifth male pleopods and all female pleopods uniramous,reduced to unsegmented plate, increasing in length from first to fifth. Fourthpleopod of male biramous; endopod reduced to unsegmented lobe; exopod long, almoststraight, 2-segmented; proximal segment long, armed on each distal corner withseta (occasionally without one or both setae), distal segment short, armed with twolong, strong subequal terminal setae and one short seta on distal corner, or without thisseta. Endopod or uropod armed with spines throughout length of inner margin fromstatocyst almost to apex. Telson elongate, triangular, with narrowly rounded apex orlinguiform, with lateral margins bearing subequal spines.The genus comprises one species.1. Hemiacanthomysis dimorpha (Ii, 1936)(Pl. XIII, figs. 5–9).Ii, 1936: 593 (Acanthomysis dimorpha); Fukuoka & Murano, 2002: 210–214 (Hemiacanthomysisdimorpha).Description. Antennal scale 3.4–5.4 times as long as broad. Carpo-propodus ofendopod of thoracopods 5–8 consists of 3–5 (in juveniles) to 4–7 subjoints. Exopod offourth pleopod of male 3 (in immature males) to 1.3 times as long as endopod; basal(proximal) segment of exopod 4–7 times as long as distal one. Inner margin of endopodof uropod armed with row of 14 (in juveniles) to 31 spines extending from statocystalmost to apex. Telson 1.4–2.7 times as long as broad at base; apex armed with 3–4 pairs of equal spines in females, with 2 pairs of spines in males; outer pair twicelonger than inner one or than lateral spines. Maximum length of females 25.7 mm, ofmales 17.6 mm.Distribution. H. dimorpha is a West Pacific widespread boreal species. It is distributedfrom the Korea Strait to the northern Bering Sea: Tkachen Bay (64°25′N;172°48′W). It has been recorded from the Sea of Japan near the Korea Strait and in theTatar Strait.Habitat and breeding. The species is sublittoral, vertically distributed from 10to 140 m, in the Sea of Japan from 10 to 104 m. It occurs in waters with a temperaturerange between -1.7° and +19°C and a salinity range between 28.44 and 34.5‰, oversand, silt, gravel with pebbles, rarer over clay. Females with embryos were registeredin the Sea of Japan July through August. The number of embryos ranges from 13 to49.59