"Leptocollonia thielei n.sp., Pl. V, fig. 9
Shell small, depressed-turbinate, perforate, dull yellowish buff, sculptured with narrow prominently raised spiral ridges. Whorls rounded, four, including the protoconch which is apparently one slightly convex and smooth whorl (protoconch eroded in all examples). First post- nuclear whorl with two spiral ridges, penultimate with from six to eight (seven plus an incipient eighth in holotype), body-whorl with fifteen, last two bordering the umbilicus, weak. The spirals are rounded but narrow and prominently raised with interspaces of from three to four times their width. The whole surface is crowded with delicate axial growth striae. Umbilicus narrow and deep, about one-ninth the major diameter, but half-obscured by the thin reflexed outer edge of the columellar callus. Peristome continued across the parietal wall by a thin glaze. Outer-basal lip thin and corrugated by the terminal points of the external spiral sculpture. The operculum is calcareous and multispiral of about seven whorls. Externally dull white, concave and deeply spirally channelled. Internally smooth and convex with a yellowish chitinous layer. The edge is thick, bevelled, with a median groove.
Diameter 9.0 mm.; height 7.5 mm. (holotype).
DENTITION. Fig. G, 13, p. 189. The radulae of these small Turbinids are most difficult to interpret on account of the minute size of the teeth and the complicated in which the bases overlap. My conclusions were made prior to reference to the results arrived at by Troschel & Thiele (1878, p. 213, pl. 22, fig. 7) and Tryon & Pilsbry (1888, pl. 60, fig. 73). The Leptocollonia theilei radula (Fig. G, 13) shows a marked resemblance to Pilsbry’s figure of that of Homalopoma carpenteri (Fig, G, 14), and is almost totally at variance with Troschel and Thiele’s interpretation based upon ‘coccineus Deshaye’, the same species. The ‘double-decked’ appearance of the central tooth is not paralleled in any other known group. In both Homalopoma and Leptocollonia this tooth has a projecting plate above as well as below, and lateral wings form a broad arc across the median area. The central appears to be functionless, for it bears no cusps, just an irregular thickening at the crest of the median arc. The laterals, five in number, are long, excavated on the inner side to accommodate the lateral wings of the central, and produced on the outer side. These features are well developed in four of the laterals, but not in the fifth.
TYPE LOCALITY. St. 153. Off Cumberland Bay, South Georgia, 54° 08' 30" S, 36° 27' 30" W, 17 Jan. 1927, 106 m.
St. 20. 14.6 miles N 41° E of Cape Saunders, South Georgia, 4 Mar. 1926, 200 m.
St. 42. Off mouth of Cumberland Bay, South Georgia, 1 Apr. 1926, 120-204 m.
St. 140. Stromness Harbour to Larsen Point, South Georgia, 23 Dec. 1926, 122-136 m.
St. 156. North of South Georgia 53° 51’ S, 36° 21’ 30” W, 20 Jan. 1927, 200-236 m.
St. 190. Bismarck Strait, Palmer Archipelago, 24 Mar. 1927, 315 m.”
(Powell, 1951: 105-106)
Leptocollonia thielei is a species of small sea snail with calcareous opercula, a marine gastropod mollusk in the family Colloniidae.[1][2]
The colorless shell grows to a height of 7 mm. It has a thin shell. It has a depressed-turbinate shape.
This marine species occurs off the South Georgia Islands and the Antarctic Peninsula.[1]
Leptocollonia thielei is a species of small sea snail with calcareous opercula, a marine gastropod mollusk in the family Colloniidae.
