Anatoma aupouria ( Powell, 1937 )

Geiger, Daniel L. & Jansen, Patty, 2004, Revision of the Australian species of Anatomidae (Mollusca: Gastropoda: Vetigastropoda), Zootaxa 415 (415), pp. 1-35 : 7-9

Anatoma aupouria ( Powell, 1937) : Figures 1–2

Schizotrochus aupouria Powell, 1937: 176 , pl. 49, fig. 3.

Anatoma aupouria: Powell, 1979: 35–36 , pl. 4, fig. 2.

Type material. HOLOTYPE ( BMNH 1962952 : A. Campbell, pers. comm.), 1.25 x 0.9 mm (W x H).

Type locality. Off Three King Islands [, New Zealand], St. 933, 260 m (OD) .

Etymology. Aupouri: Referring to a northern Maori tribe in New Zealand (Bruce Marshall, pers. comm.).

Description. Shell medium size (to 1.25 mm), somewhat turreted. Protoconch 3/4 whorls, with flocculant sculpture, no varix. Teleoconch I of 1/4 whorl, approximately 7 axials. Teleoconch II more than 1.5 whorls. Shoulder with many fine axials; axials variably internested, producing complex patterns. Axials intersected with approximately 6–8 spirals in central third of shoulder. Base with similarly complex pattern of axials and finer spirals. Underside of keel typically with supernumerary fine axials. Umbilicus open, deep, continuously sloping from base, with funiculus. Selenizone at periphery, keels strong, with strong growth increments. Margins of slit somewhat converging towards aperture. Aperture subquadratic, somewhat flared, particularly towards umbilicus where apertural margin fuses with funiculus. Animal unknown.

Differential diagnosis. Thieleella equatoria , from Tonga and Christmas Island, shares the dense axial sculpture, but has a protoconch with reticulate sculpture, is more globular in general outline, and lacks the funiculus in the umbilicus. Anatoma turbinata , ranging from Japan to Australia, is much more turreted, has a proportionally smaller aperture, and lacks a funiculus in the umbilicus.

Distribution: New Zealand, Lord Howe Island, and Norfolk Island, 31–805 m (shells only).

Specimen records.

Norfolk Island. 31 m, off Duncombe Bay , 29°S, 167.933°E ( AMS C.378320, 1) .

New Zealand. 805 m, N of Three Kings Islands , 34°S, 171.917°E ( AMS C.402696, 1) .

Australia. 44 m, Lord Howe Rise , Lord Howe Island, 31.637°S, 159.06°E ( AMS C.404151, 1) .

Remarks. The drawings of Powell (1937, 1979) show discrete spiral keels on the base, none of which are apparent on the shell; only excessive artistic license can explain the discrepancy. Most records of the species are from New Zealand, with only a few specimens have been recorded from Australian waters. Additional specimens and locality records are in the Museum of New Zealand, Te Papa Tongarewa, Wellington.

Figures

FIGURE 1. Anatoma aupouria. AMS C.402696. 805 m, N of Three Kings Islands, New Zealand. Scale bar shell = 200 µm. Specimen identified by Bruce Marshall. Scale bar protoconch = 50 µm.

FIGURE 2. Anatoma aupouria. A. AMS C.378320. 31 m, off Duncombe Bay, Norfolk Island. B. AMS C.404151. 44 m, Lord Howe Rise, Lord Howe Island. Scale bars shell = 200 µm.