Menestho schikovi Nekhaev 2017, sp. n.
Menestho schikovi Nekhaev sp. n. Menestho truncatula: Kantor & Sysoev 2006: 243 fig. 122С (partly), non Odhner, 1915. Type material. holotype (empty shell) (Figs 1A, 2 A, I), 3.12.2015, van Veen grab, ZIN 62135 /1, 6 paratypes (empty shells) from the same sample ZIN 62136 /2 and 2 paratypes (emp...
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| Format: | Other/Unknown Material |
| Language: | unknown |
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2017
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| Online Access: | https://zenodo.org/record/6021783 https://doi.org/10.5281/zenodo.6021783 |
| Summary: | Menestho schikovi Nekhaev sp. n. Menestho truncatula: Kantor & Sysoev 2006: 243 fig. 122С (partly), non Odhner, 1915. Type material. holotype (empty shell) (Figs 1A, 2 A, I), 3.12.2015, van Veen grab, ZIN 62135 /1, 6 paratypes (empty shells) from the same sample ZIN 62136 /2 and 2 paratypes (empty shells) from the same sample LMBI IN- 3. Type locality. Svalbard, Spitsbergen Island, Billefjorden, R / V Dalnie Zelentsy, sta. 44, 78°39.6'N, 16°40.4'E, 188 m. Other examined material: 3 spms, 2 shells, Kara Sea, 76°41'N, 88°14'E, 45 m, R/V G. Sedov, leg. Vagin, 0 6.09.1934, ZIN 22732 (studied with SEM); 4 spms, Kara Sea, 75°40'N, 80°26'E, 42 m, R/V G. Sedov, leg. Vagin, 0 9.09.1934, ZIN 35691; 3 spms, Kara Sea, 76°17'N, 75°08'E, 75 m, R/V G. Sedov, leg. Vagin, 21.09.1934, ZIN 35693; 1 spm, Severnaya Zemlya, 80°30'N, 90°03’E, 174 m, R/V Fyodor Litke, 29.09.1948, ZIN 35701; 1 spm,Laptev Sea, 77°25'N, 115°48'E, 62 m, R/V Sadko, leg. G.P. Gorbunov, 16.08.1937, ZIN 35696; 2 spms, Laptev Sea, 76°36'N, 118°30'E, 51 m, R/V Sadko, leg. G.P. Gorbunov, 0 2.10.1937, ZIN 35697; 1 spm, 71°24'78''N, 174°22'03''E, 585 m, R/V Professor Chromov, 22.08.2004, ZIN 60879. Diagnosis: Menestho with conical shell, convex, evenly rounded whorls, open umbilicus and straight growth-lines. Description: Shell small, conical, white or yellowish with convex, evenly rounded whorls divided by deep suture (Figs. 1 A, C, E, 2A). Shell surface with fine, frequent (8–11 on body whorl), spiral ribs, almost semicircular in section, divided by very narrow interspaces (Fig. 2I). Axial sculpture, except for straight growth-lines (Fig. 2A, I) absent. Embryonic shell intorted, of type B, partially eroded on studied specimens, smooth or with very low pattern of spiral sculpture (Fig. 2G). Aperture oval with acute angle in upper part, no teeth or folds on columella. Umbilicus clearly visible, narrow. Operculum transparent, without peg (Fig. 2E). Measurements of holotype: shell height = 3.6 mm, aperture height = 1.2 mm, last whorl height = 2.3 mm, shell width ... |
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