Erronea ovum

Not to be confused with Ovula ovum, also commonly called the egg cowry.

Erronea ovum, common name the egg cowry, is a species of sea snail, a cowry, a marine gastropod mollusk in the family Cypraeidae, the cowries.

Erronea ovum
A shell of Erronea ovum from Solomon Islands, anterior end towards the right
Scientific classification
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Gastropoda
Subclass:	Caenogastropoda
Order:	Littorinimorpha
Family:	Cypraeidae
Genus:	Erronea
Species:	E. ovum
Binomial name
Erronea ovum Gmelin 1791
Synonyms
Cypraea ovum Gmelin 1791 Erronea ovum ovum (Gmelin, 1791)· accepted, alternate representation

Description

The shells of these quite common cowries reach on average 22–26 millimetres (0.87–1.02 in) of length, with a minimum size of 16 millimetres (0.63 in) and a maximum size of 41 millimetres (1.6 in). The dorsum surface of Erronea ovum is smooth, shiny and generally dark brown, dark olive green or greyish, often with a darker wide trasversal band. They are egg-shaped (hence the Latin name ovum, meaning egg). The base and the margins are usually white or pale brown, with yellowish teeth, but in Erronea ovum chrysostoma the teeth are pink-orange. In the living cowries mantle is greyish, with long tree-shaped sensorial papillae.

A lateral view of a shell of Erronea ovum from the Solomon Islands, anterior end towards the right

A dorsal view of shells of Erronea ovum from the Solomon Islands, anterior end towards the right

Distribution

This species occurs from Southeast Asia to the Southwest Pacific, along the coasts of Japan, East China, Thailand, Indonesia, Malaysia, Papua-New Guinea, western Australia, Philippines, Palau Islands, Solomon Islands, Micronesia and New Caledonia.

Habitat

Erronea ovum lives in the tropical and subtropical zone, in shallow intertidal water up to 3–10 metres (9.8–32.8 ft) of depth, mainly on coral reefs.

Subspecies

• Erronea ovum chrysostoma (F.A. Schilder, 1927)
• Erronea ovum erici Lorenz, Bridges & Chiapponi, 2011
• Erronea ovum ovum (Gmelin, 1791) : synonym of Erronea ovum (Gmelin, 1791)
• Erronea ovum palauensis (F.A. Schilder & M. Schilder, 1938)

References

• Lorenz F., Bridges R.J. & Chiapponi M. (2011) A close look at Erronea ovum (Gmelin, 1791) with the description of a new subspecies (Gastropoda: Cypraeidae). Conchylia 41(2): 2–9. [April 2011]

External links

• Biolib
• Ovum
• Erronea ovum
• Media related to Erronea ovum at Wikimedia Commons