Scissurella lorenzi, Geiger, Daniel L., 2006

Geiger, Daniel L., 2006, Eight new species of Scissurellidae and Anatomidae (Mollusca: Gastropoda: Vetigastropoda) from around the world, with discussion of two new senior synonyms, Zootaxa 1128, pp. 1-33 : 7-9

Scissurella lorenzi new species: Figures 5 –6

Type material. Holotype SBMNH 350876. Paratype SBMNH 350879, from type locality.

Type locality. 15–35 m, Baudisson Bay, Kavieng, New Ireland, Papua New Guinea, 2.743°S, 150.658°E.

Etymology. Named for the collector of the type material, Felix Lorenz jr., Germany.

Description. Shell globular, to 1.22 mm (holotype). Protoconch of 0.75 whorls, fine axial sculpture, broadly anastomosing on embryonic cap, with faint spiral zigzag line; apertural varix well developed, connected to embryonic cap; apertural margin sinusoid. Teleoconch I 1.125–1.3 whorls (1.25 in holotype), approximately 29–35 axials (30 in holotype), spirals absent to indistinct towards beginning of selenizone. Teleoconch II of 1.0–1.25 whorls (1.25 in holotype), shoulder with axials becoming weaker and/or more widely spaced with distance from start of selenizone, 2–4 irregular spirals, 2–6 additional very weak spirals gaining prominence towards apertural margin. Under light microscope, on shoulder of teleoconch II darker and lighter radial bands, approximately eight pairs on last half of body whorl. Base with more distinct axials compared to teleoconch II shoulder, less distinct compared to teleoconch I, axials on shoulder and base mostly coordinated; approximately 15 spirals of unequal strength, on average similar to axials, producing reticulate pattern. Base sloping continuously to narrow, open umbilicus. Umbilicus with very thin funiculus from broadened parietal wall of aperture. Selenizone above periphery, slit open, margins parallel, keels moderately strong, moderately elevated. Aperture round with overhanging roof. Animal unknown.

Differential diagnosis. Scissurella staminea ( A. Adams, 1862) from Japan has a protoconch with strong axials, the axial sculpture on teleoconch II remains the same strength, while there are fewer axials per whorl, the transition of the base to the umbilicus is bordered by a distinct carina, and there is no banding pattern on the shoulder of teleoconch II. Scissurella declinans Watson, 1886 , with broad tropical Pacific distribution, has a protoconch with strong axials, the transition of the base to the umbilicus is bordered by a distinct carina, and there is no banding pattern on the shoulder of teleoconch II. Scissurella evaensis Bandel, 1998 and Sci. cebuana ( Bandel, 1998) from the Indo­ Malayan Archipelago both have strong projecting sculpture not seen in Sci. lorenzi .

Distribution. Indo­Malayan archipelago from southern Japan to Papua New Guinea (26.5°N to 5°S).

Specimen records (including non­type material). 1 km WNW of Onna Village (moon rock entry point), Okinawa, Japan, 26.497°N, 127.843°E ( LACM 78–29, 1). 1 km WNW of Onna Village (Horseshoe South), Okinawa, Japan, 26.495°N, 127.843°E ( LACM 78–99, 1). 46–55 m, 1 km WNW of Onna Village (Horseshoe Cliffs), Okinawa, Japan, 26.493°N, 127.842°E ( LACM 79–75, 2). 33 m, 1 km W Onna Village, Okinawa, Japan, 127.843°N, 127.843°E ( LACM 78–20, 1). 92 m, Okinawa, Onna Village, Japan, 26.493°N, 127.493°E ( LACM 78–101, 2). Naupapu Island, Vavaa Group, Tonga, 18.7°S, 174.1°E ( LACM 85–89, 1). 15–35 m, Baudisson Bay, Kavieng, New Ireland, Papua New Guinea, 2.743°S, 150.658°E ( SBMNH 350876, 1; SBMNH 350879, 1). 28 m, off Big Malu Malu Island, Kimbe Bay, New Britain, Papua New Guinea, 5.231°S, 150.098°E (DLG 399, 1).

Remarks: The species is easier to recognize under the light microscope due to the unique pattern of dark and light radial bands on teleoconch II. This banding pattern is often not discernible in the SEM. All specimens have been found in sand and coral rubble.

Figures

FIGURE 5. Holotype of Scissurella lorenzi new species (SBMNH 350876). Uncoated specimen, low kV SEM (1 kV). Scale bar shell = 1 mm. Scale bar protoconch = 100 µm.