| Summary: | Volutopsius nanus n. sp. Figures 19 A–C urn:lsid:zoobank.org:act: B6C52DEE-CFE6-4858-9013-AE5100D4E120 Type locality: SW of Buldir Island, Aleutian Is., Alaska (52°18.5 N, 175°49.0 E), 325 m (NMFS 23-199701 - 243). Type: Holotype, LACM 3588, 35.6 mm ( leg. RNC 9 Aug. 1997); Paratypes: Pt 1–3, LACM 3669, 20.8–29.5 mm. SW of Agattu Island, Near Ids. (52°13.5 N, 173°27.8 E), 169 m (NMFS 23-199701 - 229); Pt 4, SBMNH 169015, 33.4 mm. SE of Buldir Island (51°24.6 N, 175°20.0 E), 187 m (NMFS 94-200201 - 158); Pt 6, USNM 1606664, 35.1 mm. SE of Buldir Island (51°24.6 N, 175°20.0 E), 187 m (NMFS 94-200201 - 158); Pt 7, RNC 4711, 40.0 mm. (Type locality). Referred material: RNC 4888, 1 sp., 36.8 mm. SW of Agattu Island, Near Ids. (52°13.5 N, 173°27.8 E), 169 m (NMFS 23-199701 - 229); RNC 4901, 15.34 mm. ESE of Buldir Island (52°20.61 N, 176°22.79 E), 227 m (23- 2000-01-173). Description: Small for genus, height to 40.0 mm; suture moderately impressed, whorls rounded. Protoconch, one whorl, 3.7–4.1 mm in diameter, with four spiral cords; teleconch with three whorls; spiral sculpture of very fine lirae, with slightly wider interspaces, about 30 on penultimate whorl, and continuing on below the suture. Aperture a little more than half of shell height, outer lip flared; canal short, broad. Operculum small, less than half of aperture height. Radula: Typical for subfamily, rachidian tooth with four subequal cusps; lateral teeth with two large, heavy cusps, outer cusp strongly curved, inner cusp straight. Remarks: This is the smallest known species of Volutopsius , and probably cannot be confused with any congeners. Volutopsius middendorffi (Dall, 1891) is similar but much larger, reaching over 11 cm, and has a pinkish protoconch. Etymology: Named for its small size, from the Latin nanus, dwarf. Volutopsius nanus is considerably smaller than all other known Volutopsinae. Distribution: This small species is restricted to the western-most Aleutians, from the vicinity of Buldir Id. (176°22 E) to Attu Id. (173° E), at depths of ...
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