Belknapchiton australis Sirenko, 2023, n. sp.
Belknapchiton australis n. sp. (Figures 7C, D, 19–22) Leptochiton cf. opiparus; Sirenko 2020: 426, figs. 32–35, 44A, B. Belknapchiton sp.; Sirenko et al. 2022: 104. Type material. Holotype (TMAG, E 45530), now disarticulated consisting of SEM stub of valves I, II, IV, V, VIII, part of perinotum and...
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| Format: | Other/Unknown Material |
| Language: | unknown |
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2023
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| Online Access: | https://zenodo.org/record/8247043 https://doi.org/10.5281/zenodo.8247043 |
| Summary: | Belknapchiton australis n. sp. (Figures 7C, D, 19–22) Leptochiton cf. opiparus; Sirenko 2020: 426, figs. 32–35, 44A, B. Belknapchiton sp.; Sirenko et al. 2022: 104. Type material. Holotype (TMAG, E 45530), now disarticulated consisting of SEM stub of valves I, II, IV, V, VIII, part of perinotum and radula, mount of part of perinotum and vial with other valves. Type locality. Australia, S Tasmania slope, 44.2012°S, 146.1992°E, 1050–1230 m. Material examined. New Zealand, Kermadec Islands, NNE of Herald Islets, Raoul Island, 29°12.00’S, 177°49.30’W, R/ V Acheron, stn 1973312, 1188–1225 m, 1 spm (NMNZ M 222132) BL 16.0 mm, 05.04.1973; Australia, S Tasmania slope, 44.2012°S, 146.1992°E, 1050–1230 m Southern Surveyor stn 50 Lot 50, Sherman sled, CSIRO, holotype (TMAG, E 45527) BL 13.0 mm, 06.04.2007. Etymology. From the Latin australis, south. Distribution. Southern Ocean, Off Tasmania and Kermadec Islands, 1188–1225 m. Diagnosis. Animal rather small, elevated, valves rather long, arched, not beaked, tail valve triangular, mucro postmedian, postmucronal slope straight; tegmentum sculptured by small triangular granules arranged in quincunx; each granule with one megalaesthete and 2–4 micraesthetes, surface between granules noticeably striated; dorsal scales sculptured with three to six fine, barely visible riblets; central teeth of radula wide, major lateral teeth with sharply pointed, unidentate head with small denticle-like appendix at inner edge; twelve gills per side. Description. Holotype (BL 13.0 mm) elongate oval in outline. Valves arched, moderately elevated (elevation ratio 0.45 in valve V), not beaked. Tegmentum white. Head valve semicircular, wider than tail valve, posterior margin widely V-shaped. Second valve oval, anterior and posterior margins convex. Other intermediate valves almost rectangular, lateral areas not raised, anterior margin slightly concave in central part, posterior margin weakly convex, lateral areas not raised. Tail valve triangular, mucro postmedian, antemucronal slope slightly convex, ... |
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