Biology:Crossea biconica

Short description: Species of gastropod

Crossea biconica
Original drawing of a shell of Crossea biconica
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Gastropoda
Subclass:	Vetigastropoda
Order:	Trochida
Superfamily:	Trochoidea
Family:	Conradiidae
Genus:	Crossea
Species:	C. biconica
Binomial name
Crossea biconica Hedley, 1902

Crossea biconica is a species of small sea snail or micromollusc, a marine gastropod mollusc in the family Conradiidae.

Description

(Original description by Charles Hedley) The height of the shell attains 1.7 mm, its diameter 1.6 mm. The minute but solid, white shell has a biconical shape. Its base is greatly produced, the periphery keeled. The four whorls are somewhat turreted.

Sculpture : The first and second whorls are smooth, the third comparatively coarsely cancellated, the fourth contains dense fine spiral cords crossed by fainter growth lines which tend to bead the interstices. The base is two-thirds of the total height. The wide and deep umbilicus is bordered by a conspicuous ridge, and has an elevated funicle winding within. The oblique aperture is rhomboidal, channelled by the umbilical ridge, and with a gutter at the termination of the funicle. A heavy outstanding varix occurs a short distance behind the aperture.

The small size, produced base, and wide umbilicus are characters which distinguish this from other Australian members of the genus.

Distribution

This marine species is endemic to Australia. It is found off the Northern Territory and Queensland

References

• Hedley, C. 1902. Studies on Australian Mollusca. Part VI. Proceedings of the Linnean Society of New South Wales 27: 7-29
• Cotton, B.C. 1959. South Australian Mollusca. Archaeogastropoda. Handbook of the Flora and Fauna of South Australia. Adelaide : South Australian Government Printer 449 pp.

External links

• To World Register of Marine Species

Wikidata ☰ Q5188539 entry