Atlanta frontieri Richter, 1993
Overview
This is a medium sized dextrally shelled, pelagic snail, 0.5 cm in diameter with large eyes and a single swimming fin. The shell is large, strongly flattened and keeled. There are 6.5 whorls. The spire is very small, and like the rest of the shell, colourless, it shows spiral sculpture. The operculum has a very small spire. It is a carnivore predating on relatively large zooplankton. This species occurs in warm waters of the W-Indian Ocean (Atlanta frontieri).
Taxonomic Description [after Richter, 1993]
The shell is colourless transparent and medium sized with up to 6.5 whorls. The spire is small with 5 whorls. The keel penetrates between the whorls and increases rapidly in height. The keel is high and surrounds 1.5 whorls. The umbilicus is relatively wide and deep. The spiral whorls have, except for the first one, a flattened upperside. The shell sides are concave. The upperside of the spire shows spiral sculpture. At the second whorl a spiral rib is found near the suture; on the third whorl a spiral rib occurs between this rib and the suture and runs onto the fourth whorl. Eyes and operculum are similar to those in Atlanta peroni. The eye lens is normal sized. The radula shows sexual dimorphism and resembles that of Atlanta peroni. The radula (2-1-1-1-2) shows with 44-50 transverse rows.
Shell diameter up to 5.5 mm.
Juveniles
The juveniles have a small, dextrally coiled shell. A special description is not available but the veliger is illustrated (Atlanta frontieri veliger).
Reproduction
In this species the sexes are separate.
Ecology
This species is an epipelagic carnivore.
Distribution
This species is found in the W-Indian Ocean.
Types
Atlanta frontieri Richter, 1993: 192, pl. 1, fig. 3, pl. 2, fig. 7, pl. 3, fig. 9, pl. 4, figs. 18, 21.
Holotype: SMF 309764 in SMFM, Paratypes: SMF 309765/5 in SMFM.
Type locality: Meteor 51 stat. 194, 0-200 m depth.