Zebinella janus is a species of small sea snail, a marine gastropod mollusk or micromollusk in the family Rissoinidae.MolluscaBase eds. (2023). MolluscaBase. Zebinella janus (C. B. Adams, 1852). Accessed through: World Register of Marine Species at: https://www.marinespecies.org/aphia.php?p=taxdetails&id=767541 on 2023-10-25
Description (Original description) The white shell is long and ovate conic. Anteriorly it is covered with fine crowded spiral striae. Elsewhere it is covered with small crowded transverse ribs, which on the body whorl appear merely as transverse stria becoming obsolete near the periphery. The apex is acute. The outlines of the spire are moderately curvilinear. It contains nine whorls, moderately convex, with a lightly impressed suture. The aperture is large, oblique, moderately effuse below, more deeply effuse above. The outer lip is much advanced along the middle, thickened by a broad stout varix. The umbilicus is wanting.Adams, C. B. (1852). Catalogue of shells collected at Panama, with notes on their synonymy, station, and habitat. Annals of the Lyceum of Natural History of New York. 5: 229-549
The type of Z. janus in the Amherst collection, collected by C. B. Adams, at Panama, is a very badly worn medium sized shell, in which the ribs have been worn down to such an extent that one can scarcely count them. There are probably 20 on each of the last 2 whorls. It is absolutely impossible to decide whether spiral sculpture may have been present or absent.Turner, R. D. (1956). The Eastern Pacific marine mollusks described by C. B. Adams. Occasional Papers on Mollusks, Museum of Comparative Zoology. 2(20): 21-135
Distribution This marine species occurs off Panama, Caribbean Sea.
References
Faber M.J. & Moolenbeek R.G. (2013) Two new species of Rissoinidae from Guadeloupe (Gastropoda: Rissooidea). Miscellanea Malacologica 6(1): 9-14
External links Bartsch, P. (1915). The Recent and fossil mollusks of the genus Rissoina from the west coast of America. Proceedings of the United States National Museum. 49 (2094): 33-62, plates 28-33