Anatoma kopua, Geiger, Daniel L. & Marshall, Bruce A., 2012

Geiger, Daniel L. & Marshall, Bruce A., 2012, New species of Scissurellidae, Anatomidae, and Larocheidae (Mollusca: Gastropoda: Vetigastropoda) from New Zealand and beyond, Zootaxa 3344, pp. 1-33 : 21-22

Anatoma kopua new species

(Figures 16–17)

Type material. Holotype ( NMNZ M.174848: Fig. 16). 4.26 × 4.53 mm. Paratypes: off Sydney, New South Wales, Australia, 33.600˚S, 152.083˚E, 1143– 1106 m (AMS C.453747, 5: Fig. 17 A); Lord Howe Rise, SE of Lord Howe Island, Tasman Sea, 34.272˚S, 163.102˚E, 1186 m ( NMNZ M.174864, 1: Fig. 17 B); Challenger Plateau, New Zealand, 40.835˚S, 168.247˚E, 1005–1009 m ( NMNZ M.174847, 1: Fig. 17 C).

Type locality. Challenger Plateau, New Zealand, 40.713˚S, 167.933˚E, 1029 m, 18 Apr. 1980, RV Tangaroa , foraminiferal ooze.

Etymology. Deep ( New Zealand Maori). Adjective.

Description. Shell large (4.27 × 4.58 mm: Figs 16–17), trochiform biconical turreted. Protoconch large (275 µm), 0.75 whorl, flocculent sculpture, no apertural varix, apertural margin straight. Teleoconch I of 0.3–0.4 whorl, 12–15 axial cords, spiral cord in position of selenizone. Teleoconch II of 4 whorls, suture moderately impressed, sutsel less than width of selenizone on early whorls, about twice as wide as selenizone at apertural margin of large specimen. Shoulder moderately convex, regular axial cords, approximately 40 on first whorl, interstices about 4 times as wide as cords; after 1–2 teleoconch II whorls, about 2–5 at apertural margin, irregularly spaced. Base with constriction below selenizone, same strength and density of axial cords, spiral threads regularly spaced, stronger than those on shoulder, approximately 20, noticeable absence of spirals from a gap immediately below selenizone. Umbilicus open, narrow, obscured by reflexed adumbilical portion of peristome. Selenizone slightly above periphery, rather wide, lunules rather strong, keels moderately strong, rather elevated ( Fig. 17 A). Animal unknown.

Figure 16. Anatoma kopua new species. Holotype. Challenger Plateau, New Zealand, 1029 m (NMNZ M.174848). Scale bar shell = 1 mm. Scale bar protoconch = 100 µm.

Distribution. New South Wales, Australia and New Zealand, approximately 1000 m.

Remarks. Anatoma equatoria from the Indo-Malayan Archipelago has a more turreted shell shape, has spiral threads on the base immediately below the selenizone, and has a more inflated base. Anatoma flexidentata Geiger & Sasaki, 2008 from the Indo-West Pacific has a shorter teleoconch I (0.3 vs. 0.5 whorl), has a more globular whorl profile, and has spiral threads on the base immediately below the selenizone. Anatoma maxima (Schepmann, 1908) from the Indo-Malayan Archipelago and Western Pacific has the selenizone closer to the periphery, has an overall more discoidal shell shape, and has at least four times as many spiral threads on the shoulder. Anatoma aedonia (Watson, 1886) from the Caribbean and off Brazil has a more turreted overall shell shape, a wider sutsel on early whorls (2× vs. 1× widths of selenizone), has a longer teleoconch I (0.75–1 vs. 0.5 whorl), and has a narrower selenizone. Anatoma amoena (Thiele, 1912) from Antarctica has a protoconch with reticulate sculpture, a longer teleoconch I (1 vs. 0.5 whorl), and has spiral threads immediately below the selenizone on the base.

Figures

FIGURE 17. Anatoma kopua new species. Paratypes. A. Off Sydney, New South Wales, Australia, 1143 – 1106 m (AMS C. 453747). B. Lord Howe Rise, SE of Lord Howe Island, Tasman Sea, 1186 m (NMNZ M. 174864). C. Challenger Plateau, New Zealand, 1005 – 1009 m (NMNZ M. 174847). Scale bar shell = 1 mm. Scale bar protoconch = 100 µm.