Anatoma micalii is a species of minute sea snail, a marine gastropod mollusc or micromollusc in the family Anatomidae.
The species was described by malacologist David L. Geiger in 2012 in his comprehensive monograph on little slit shells (Scissurelloidea and related groups). It is placed in the genus Anatoma within the family Anatomidae.
The shell is small, typically attaining a length (or diameter) of 0.6âÂÂ1 mm, occasionally up to around 1.5 mm in comparative contexts. It is biconic to globose in outline with a low to moderately elevated spire of about 2âÂÂ2â  whorls. The protoconch is spotted or distinctly sculptured. The teleoconch features a prominent, raised selenizone (a characteristic slit-band in this family) positioned high on the whorls. Sculpture on the upper part of the last whorl consists of 30âÂÂ40 coarse axial ribs, markedly coarser than in similar congeners (e.g., compared to forms with 60âÂÂ70 fine riblets). The shell is generally pearly white and delicate.
A. micalii differs from related species (such as undescribed forms from Skerki Bank or A. tenuisculpta) by its raised selenizone and coarser teleoconch sculpture.
This species is endemic to the Mediterranean Sea, primarily in the central and eastern basins. The type locality is the Strait of Messina, Italy. It has been recorded from:
It occurs in the Mediterranean proper and is not known from extra-Mediterranean waters.
The species inhabits subtidal zones from the lower photic zone to continental shelf depths (documented around 120 m in some records), typically on hard substrates or in association with coralligenous or rocky environments typical for slit shells.