Anatoma regia is a species of small sea snail, a marine gastropod mollusc in the family Anatomidae.
Description The height of the shell attains 2.5 mm, its width 2 mm.
(Original description) This small, turbinate shell features three slightly angled whorls, with the upper surface lightly convex and the underside more so; the body whorl is notably large. The protoconch consists of two minute, smooth, dull whorls.
Sculpture: The shell exhibits two fine, sharp, raised spiral keels positioned closely together on the angle of the whorls. Fine flexuous riblets adorn both surfaces. On the underside, these riblets are crossed by fine spiral lirae, which become more distinct around the umbilicus.
The umbilicus is small and open, and the aperture is obscurely triangular. The anal slit, located between the keels on the outer lip, is long and more contracted at the edge of the lip than at its upper end. The operculum remains unknown. The shell's color is white.Mestayer, M. K. (1916). Preliminary list of Mollusca from dredgings taken off the northern coasts of New Zealand. Transactions of the New Zealand Institute 48: 122–128
Distribution This marine species is endemic to New Zealand and occurs off North Island, South Island, Lord Howe Rise, Chatham Islands, Campbell Plateau and Pukaki Rise.
References
Powell A. W. B., New Zealand Mollusca, William Collins Publishers Ltd, Auckland, New Zealand 1979 Rosenberg, G. 1992. Encyclopedia of Seashells. Dorset: New York. 224 pp. page(s): 35 Geiger D.L. (2012) Monograph of the little slit shells. Volume 1. Introduction, Scissurellidae. pp. 1-728. Volume 2. Anatomidae, Larocheidae, Depressizonidae, Sutilizonidae, Temnocinclidae. pp. 729–1291. Santa Barbara Museum of Natural History Monographs Number 7 Spencer, H.G., Marshall, B.A. & Willan, R.C. (2009). Checklist of New Zealand living Mollusca. Pp 196-219. in: Gordon, D.P. (ed.) New Zealand inventory of biodiversity. Volume one. Kingdom Animalia: Radiata, Lophotrochozoa, Deuterostomia. Canterbury University Press, Christchurch.