Astralium rotularium

Astralium rotularium, common name the rotary star shell or the knob star shell, is a species of sea snail, a marine gastropod mollusk in the family Turbinidae, the turban snails.^[2][3]

Astralium rotularium
Apertural view of Astralium rotularium
Scientific classification
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Gastropoda
Subclass:	Vetigastropoda
Order:	Trochida
Superfamily:	Trochoidea
Family:	Turbinidae
Genus:	Astralium
Species:	A. rotularium
Binomial name
Astralium rotularium (Lamarck, 1822)[1]
Synonyms[2]
Trochus rotularius Lamarck, 1822

Description

The size of the shell varies between 25 mm and 50 mm. The white, subdepressed, imperforate shell has a conoid shape. The spire is subacute. The six whorls are obliquely finely costulate with numerous prominent imbricating laterally compressed plicae at the sutures. The body whorl is carinated with plicate-nodose carina. The base of the shell is convex, squamosely concentrically lirate. The white columella is arcuate, not dentate. The aperture is oblique.^[4]

Distribution

This marine species is endemic to Australia and occurs off the Northern Territory, Queensland and Western Australia