Atlanta meteori Richter, 1972b
Overview
This is a large dextrally shelled, pelagic snail, 0.4 cm in diameter with by large eyes and a single swimming fin. The colourless shell is strongly flattened and keeled. The spire is small, slightly oblique, and smooth. The spire of the operculum is relatively small. It is a carnivore predating on relatively large zooplankton. This species occurs in the warm water of the Indian Ocean (Atlanta meteori 1).
Taxonomic Description [after Richter, 1990]
The shell is colourless, smooth, very thin and fragile. The keel penetrates over half a whorl distance between the preceding whorls. The keel is high and slopes gradually far before the aperture. The body whorl has transverse waves. The spire is small, slightly oblique. The umbilicus is narrow. The top angle is 70°, the suture is shallow (Atlanta meteori). The inner whorls of the spire are not decalcified. The eyes (type B), operculum (type B) and radula resembles A. gibbosa. The width increase angle of the radula is 12-14°. Sexual dimorphism in radula and shell is absent.
Shell diameter up to 4 mm.
Juveniles
The juveniles have a small, dextrally coiled shell. The Atlanta meteori juvenile is characterised by a conical shell with a relatively sharp top, as also seen in the photograph of the Atlanta meteori veliger. The Atlanta meteori protoconch is smooth with a very shallow suture, the embryonic shell is strongly declined and nearly completely separated form the last whorl by the deeply penetrating keel as seen in the Atlanta meteori young.
Reproduction
In this form the sexes are separate.
Ecology
This species is carnivorous and epipelagic.
Distribution
This species occurs in the Indian and Pacific Oceans, see the Atlanta meteori map.
Types
Atlanta meteori Richter, 1972: 88, fig. 2, 11.
Holotype: SMF 223050. Paratypes: SMF 223051/4 all preserved in the SMFM.
Type locality: Indian Ocean.