Boreancistrolepis excelsus Mclean & Clark 2023
- Dataset
- Seven new genera and thirty-four new species of buccinoid gastropods (Neogastropoda: Buccinidae) from the Aleutian Islands, Alaska
- Rank
- SPECIES
- Published in
- Mclean, James H., Clark, Roger N. (2023): Seven new genera and thirty-four new species of buccinoid gastropods (Neogastropoda: Buccinidae) from the Aleutian Islands, Alaska. Zootaxa 5351 (2): 151-201, DOI: 10.11646/zootaxa.5351.2.1, URL: http://dx.doi.org/10.11646/zootaxa.5351.2.1
Classification
- kingdom
- Animalia
- phylum
- Mollusca
- class
- Gastropoda
- order
- Neogastropoda
- family
- Colidae
- genus
- Boreancistrolepis
- species
- Boreancistrolepis excelsus
description
Description: Shell relatively large (largest examined 80.7 mm, RNC 4522), profile tall, moderately slender, whorls six (figs. 5 B – D); shell white, periostracum glossy, thin, adherent, olive green, with slightly lighter zone on the basal region, shiny, not flaking in dry shells; Protoconch one whorl; whorls rounded; irregular, sculpture of oblique, spiral cords (especially near the shoulder) very weak or absent; aperture about 40 % of shell height, notch shallow; outer lip extending well below the base of the pillar, parietal callus white, well-marked but not raised; continuous lip thickening extending to the parietal shield and columella of mature shells; canal very short; Operculum (fig. 5 E), convex, glossy, with terminal nucleus. Radula (fig. 2 F). Rachidian tooth broad, bearing three relatively long, sharply pointed cusps, the central cusp somewhat larger than the lateral ones. Lateral teeth long, bearing three well-spaced, sharply pointed cusps; outer denticle large, curved; central cusp about half as long as outer one; inner cusp somewhat longer than the central one, strongly curved.
description
Figures 5 B – F urn: lsid: zoobank. org: act: D 0 FD 5604 - C 34 D- 48 A 4 - BA 7 D-C 350 D 464604 F
discussion
Remarks: Paratypes agree with holotype in all characters, and individual variation is very minor, some specimens have erosion at the suture giving channeled appearance. This genus / species bears a striking resemblance Aleutijapelion aleuticus (Dall, 1895) in its profile, and two-toned periostracum, but differs in having a glossier periostracum, convex, glossy operculum, low (not extended), nuclear whorls, and radular teeth typical of members of Parancistrolepidinae (Rachidian tooth bearing three, sharply pointed cusps, as opposed to a simple, acuspate plate in Beringiinae). The new species also resembles Neancistrolepis glaber Habe & Ito, 1973 (fig. 5 A), but differs in its smaller size (80 mm verses 130 + mm), heavier, thicker shell, and larger, glossy operculum which fills the aperture. Baxter (1987: 120) reported on this species (as Beringius aleuticus Dall, 1895), stating that “ Beringius aleuticus does not belong in the genus Beringius based on its nuclear whorls and what is apparently its operculum ”.
distribution
Distribution: Occurs throughout the Aleutian Islands, from Unalaska Island, Fox Ids. (166 ° 49 W), west to the type locality, at Attu Island, Near Ids. (173 ° 27 E), at depths of 145 – 407 m. Habitat: Black sand and gravel, with bottom temperatures of 3.4 – 4.8 ° C.
etymology
Etymology: From the Latin, meaning exalted.
materials_examined
Type locality: S of Attu, Island, Near Islands, Aleutian Islands, Alaska (52 ° 13.5 N, 173 ° 27.8 E), 169 m, (NMFS 23 - 1997 - 01 - 229) (leg. RNC, 6 August, 1997, trawled, R / V Dominator). Type material: Holotype, LACM 3570, 69.0 mm (leg. RNC, 6 August, 1997; trawled, R / V Dominator); Paratypes: Pt 1, LACM 3608 (type locality), 74.4 mm; Pt 2, LACM 3609, 58.1 mm. Tanadak Pass, E of Segula Island, Rat Ids. (52 ° 03.45 N, 178 ° 18.94), 407 m; Pt 3, USNM 1606663, 68.38 mm. E of Kruloi Point, Agattu Island, Near Ids. (52 ° 27.91 N, 174 ° 13.71 E), 118 m, (NMFS 94 - 2002 - 01 - 161); Pt 4, SBMNH 46499, 64.11 mm. S of Amutka Island (52 ° 29.46 N, 171 ° 06.96 W), 281 m, (NMFS 176 - 2014 - 01 - 40); Pt 5, SBMNH 169000, 64.4 mm. S of Little Sitkin Island, Rat Ids. (51 ° 52.56 N, 178 ° 34.01 E), 407 m, (NMFS 94 - 2002 - 01 - 154); Pt 6, CASIZ 236199, 48.64 mm. Samalga Pass (52 ° 56.1 N, 169 ° 20.38 W), 399 m, (NMFS 143 - 2004 - 01 - 23); Pt 7, RNC 4700 (type locality) 65.17 mm. Referred material: CASIZ 149895, 1 sp., 30.38 mm, S of Islands of Four Mountains (52 ° 20.45 N, 170 ° 40.08 W), 224 m, (NMFS 94 - 200001 - 48); RNC 4522 (type locality), 3 sp., 28.19 – 80.78 mm; RNC 4623, 1 sp., 69.38 mm. S of Unalaska Island (53 ° 12.0 N, 166 ° 49.82 W), 209 m, (134 - 2003 - 01 - 17); Koen Fraussen Coll., 1 sp., 67.97 mm. S of Yunaska Island (52 ° 29.68 N, 170 ° 41.19 W), 226 m, (NMFS 23 - 1997 - 01 - 48); RNC 4690, 1 sp., 26.86 mm. S of Seguam Island (52 ° 03.51 N, 172 ° 33.12 W), 145 m, (NMFS 23 - 2000 - 01 - 72); RNC 4917, 2 sp., 68.27 & 39.19 mm S of Islands of four Mountains (52 ° 13.7 N, 169 ° 44.7 W), 329 m, (NMFS 143 - 2010 - 01 - 72).