биота российских вод японского моря - Materials of Alexey Shipunov

However, these differences sometimes are barely perceptible, and in such cases it ishard to distinguish these species.Geographical distribution. A. alaskensis is distributed along Alaska andKamchatka shores, near the Commander Islands and in the Tatar Strait.Vertical distribution. The species is sublittoral, occurring to a depth of 180 m.5. Achelia gracilipes (Cole, 1904)(Pl. XII, figs. 1–5)Cole, 1904: 269–270, pl. 12, fig. 5, pl. 18, figs. 1–6 (Ammothea gracilipes); Losina-Losinsky, 1933: 60–61, fig. 11 (Ammothea gracilipes var. borealis); Nesis, 1967: 250 (Acheliagracilipes).Description. Trunk oval, unsegmented; cephalic segment slightly expandedanteriorly; corners rounded, with small unarmed tubercles. Lateral processescontiguous, each bearing small conical tubercle on distal margin of dorsal side. Oculartubercle low, conical; eyes in its middle part. Proboscis equal to trunk in length,pyriform, consists of short basal part and ovoid distal one. Abdomen rather slender,reaches distal ends of coxae 1 of 4th legs. Chelifore shorter than half of proboscis;scape bears small prominence with spine on distal end; chela as long as half of scapeor shorter. Palp 8-segmented, slightly longer than proboscis; segments 2 and 4 equal;segments 5 to 8 short, densely covered with setae on ventral side. Oviger in femalesequal in length to palp, in males twice as long as palp; segments 4 and 5 longest;segment 7 bears projection covered with setae; other 3 segments small, only segment10 bears 2 compound spines. Legs about twice as long as trunk, rather slender,especially in males; coxa 1 bears specific finger-shaped projection, almost equal tosegment’s length; coxa 2 one and half times as long as coxa 1; male coxa 2 of 3rd and4th legs bears genital spur; femur and both tibiae subequal; female femur broadened;propodus long and rather thin, gently curved and has poorly developed heel with 3curved spines and row of small spinules on sole. Main claw strong, gently curved,reaching half of propodus; auxiliary claws as long as half of main claw. Legs almostunarmed, having only few setae on coxae 2 and 3. Trunk length 1.5–2 mm, width8 mm.Remarks. The specimens collected in the Tatar Strait were referred by Losina-Losinsky to A. gracilipes var. borealis. They differ from the typical forms in theabsence of noticeable tubercles on the anterior margin of the cephalic segment, in thelonger abdomen, shorter scape, and larger body (body length – 3 mm, width of bodywith legs – 11.5 mm).Geographical distribution. A. gracilipes has been recorded along the Californiashore, off the Commander Islands, near Kamchatka, the South Kurils, and the SouthSakhalin (in the Tatar Strait).Vertical distribution. The species is found in shallow waters (to 5 m depth).6. Achelia segmentata Utinomi, 1954(Pl. XI, figs. 7–11)Utinomi, 1954: 20, fig. 9; 1971: 330; Nesis, 1967: 249.111