Alvania” nihonkaiensis Hasegawa, 2014

Hasegawa, Kazunori, 2022, Bathyal Rissoidae (Gastropoda: Rissooidea) off the Russian Far East coast of the Sea of Japan, with redescription of Punctulum reticulatum Golikov, 1986, Ruthenica, Russian Malacological Journal 32 (2), pp. 85-92 : 87

“ Alvania” nihonkaiensis Hasegawa, 2014

( Fig. 2B )

Alvania nihonkaiensis Hasegawa, 2014: 132–135 , figs 38 D–I, 39 D–F, 40 C–D, 43–45, 49H; table 8.

Material examined. SoJaBio A 2-10, MIBM 39337 (depth range: 455–456 m).

Distribution. Off Primorsky Krai coast on the northern slope, and from off Rebun Island south to off Oki Island on the southeastern slope in the Sea of Japan; off Abashiri in the Okhotsk Sea, within the depth range of 176– 635 m.

Remarks. As with the preceding one, this species is also characterized by its distinct protoconch morphology, in this case a zigzag sculpture.Although only one juvenile specimen was recognized among the present material, it was confidently identified based on this character. This is the first record of this species from the northern slope of the Sea of Japan, as well as in any Russian waters.

Figures

FIG. 2. Species of Rissoidae. A. Punctulum akibai (Yokoyama, 1926), SoJaBio stn. A2-10 (455-456 m), MIBM 39336. B. Punctulum nihonkaiensis (Hasegawa, 2014), SoJaBio stn. A2-10 (455-456 m), MIBM 39337. C-D. Frigidoalvania asura (Yokoyama, 1926), SoJaBio stn. B7-7 (470-528 m), MIBM 39340. E-F. Frigidoalvania tanseimaruae Hasegawa, 2014, SoJaBio stn. B6-7 (1,001-1,011 m). G-J. Punctulum flavum (Okutani, 1964); G-H, “shallow-water form”, SoJaBio stn. A2-10 (455-456 m), MIBM 14270; I-J, “deep-water form”, SoJaBio stn. A6-7 (2,511-2,534 m), MIBM 39334. All at the same scale; scale = 1 mm. РИС. 2.Виды Rissoidae.A. Punctulum akibai (Yokoyama,1926), SoJaBioст.A2-10 (455-456м), MIBM 39336.B. Punctulum nihonkaiensis (Hasegawa, 2014), SoJaBio ст. A2-10 (455-456 м), MIBM 39337. C-D. Frigidoalvania asura (Yokoyama, 1926), SoJaBio ст. B7-7 (470-528 м), MIBM 39340. E-F. Frigidoalvania tanseimaruae Hasegawa, 2014, SoJaBio ст. B6-7 (1001-1011 м). G-J. Punctulum flavum (Okutani, 1964); G-H, “мелководнаЯ форма”, SoJaBio ст. A2-10 (455-456 м), MIBM 14270; I-J, “глубоководнаЯ форма”, SoJaBio ст. A6-7 (2511-2534 м), MIBM 39334. Все раковины в одном масШтабе, масШтабнаЯ линейка = 1 мм.