Kingdom Animalia Class Gastropoda Superfamily Scissurelloidea Rank Species | Phylum Mollusca Clade Vetigastropoda Family Scissurellidae | |
Sukashitrochus atkinsoni is a species of minute sea snail, a marine gastropod mollusk or micromollusk in the family Scissurellidae, the little slit snails.
Contents
Description
The minute, brown shell attains a height of 2 mm. It has a globose-depressed shape. The spire is short, low, and blunt. The three whorls widen rapidly and are plane above. The last whorl descends very deeply toward the aperture, with a strong keel at the shoulder, occupied by the anal fasciole, and another keel at the periphery, the space between them concave. Below this carina there are about 3 rather separated spiral lira, and around the umbilicus three more. The keels are obsolete for a short distance behind the aperture. The fine growth striae are scarcely perceptible. The slit fasciole present on the last 1½ whorls is very narrow. Its edgesare pinched up into a strong keel. It terminates about ½ mm or ¾ mm behind the peristome in a long, narrow slot. The ovate aperture is very oblique. It is narrowed above. The columella is slightly arcuate, and nearly vertical. The umbilicus is narrowly perforated, funnel-shaped, and smooth inside. On old shells the median carina becomes rounded on the last ¾ whorl, and there are numerous spiral riblets both above and below the slit fasciole.
Distribution
This marine species occurs off Queensland to South Australia and Western Australia; off Tasmania