Neptunea aleutica Mclean & Clark 2023, n. sp.

Neptunea aleutica n. sp.

urn:lsid:zoobank.org:act: 18759E3F-4E07-448B-9461-3D0E2A6537A8

Figures 15 A–C

Type locality: S of Oglodak Island, Andreanof Ids., Aleutian Is., Alaska (51°47.93 N, 175°11.74 W), 273 m (NMFS 23-200001 - 95).

Type material: Holotype: LACM 3580, 108.5 mm (leg. 14 June, 2000, trawled, R/V Dominator); Paratypes: Pt 1, LACM 3635, 99 mm. SE of Kiska Island, Rat Ids. (51°39.54 N, 178°26.72 W) 369 m (NMFS 143-200401 - 117); Pt 2, SBMNH 464989, 72.9 mm. E of Kiska Island, Rat Ids. (51°50.22 N, 178°06.35 E), 252 m (NMFS 148-201201 - 151); Pt 3, SBMNH 464984, 71.0 mm. Amutka Pass (52°12.26 N, 171°38.84 W), 460 m (NMFS 143-201201 - 52); Pt 4 & 5, USNM 1606668, 89.5 mm & 72.7 mm. E of Kiska Island, Rat Ids. (51°50.22 N, 178°06.35 E), 252 m (NMFS 148-201201 - 151); Pts 6 & 7, CASIZ 236196, 84.2 mm & 74.8 mm. E of Kiska Island, Rat Ids. (51°50.22 N, 178°06.35 E), 252 m (NMFS 148-201201 - 151); Pt 7 & 8, RNC 4715, 107.3 mm & 72.5 mm. E of Kiska Island, rat Ids. ((51°50.22 N, 178°06.35 E), 252 m (NMFS 148-201201 - 151); Pt 9, Koen Fraussen Coll. 95.7 mm. Petrel Bank, NE of Semisopochnoi Island, Rat Ids. (52°02.32 N, 179°19.51 W), 283 m (NMFS143-201201 - 137).

Description: Shell moderately large (holotype 108.5 mm), pyriform, white with thin brown periostracum. Whorls rounded, suture moderately impressed; protoconch small, 2.2–2.6 mm in diameter, with three whorls; teleconch with four whorls, early whorls with a single carination. Axial sculpture lacking. Mature shell with about five weak primary spiral cords above suture, with one intercalary secondary cord between primary cords and finer tertiary cords between; cords of base similar, but more closely crowded and loosing distinction between primary and secondary cords. Mature lip not flared or much thickened; canal short, twisted.

Radula: Typical neptuniid, rachidian tooth broad, quadrate, indented anteriorly, bearing four equal-sized cusps. Lateral teeth tri-cuspid, cups well-spaced, outer cusp long, rather slender, curved, central cusp less than half the length of outer cusp, slightly bent, inner cusp very slightly larger than inner one, only slightly bent.

Remarks: Neptunea aleutica differs from the similar Neptunea quhmax n. sp. by 1) the thinner shell, 2) broader profile with longer aperture and less impressed suture and 3) less projecting spiral cords. Shells are often partially covered with colonies of the encrusting hydroid, Hydractinia spp.

Etymology: Name refers to the Aleutian Islands.

Distribution: Central Aleutians, Amutka Pass (171°38 W) to near Kiska Island, Rat Ids. (178°06 E) at depths of 103– 460 m.

Habitat: Found on gravel, pebble and sand/shell hash bottoms, with a temperature of 3.7°–3.9°C.