Cypraea tigris (Tiger cowrie)

Identification

One of the larger cowries and easy to recognize by the white shell with black spots. The mantle contains a pattern of very fine white and dark lines (almost like a fingerprint), with small filaments with white tips. The papillae are undivided and have a white tip.

Status

Unassessed by the IUCN Red list, but a common species of cowrie in tropical waters.

Habitat

It is found mostly in the IndoPacific up to Hawaii, but in the Indian Ocean and Red Sea as well. They can usually be found on intertidal reef platforms, seagrass beds, on sand and rubble, or barrier reefs and fringing reefs. They hide under coral rubble or under crevices and ledges, in a depth range of 0-30 meters.

Reproduction

The life history of cowries can be split into three stages: the first being the juvenile larva stage where shell volume increases, secondly the callus-building bulla stage whereby the shell is thickened and lastly the adult stage where no further growth occurs and sexual maturity is reached. Cowries sexes are separate and they practice copulation. The female deposits her eggs which are embedded in a circular gelatinous mass. The mother will then brood the egg mass for up to four weeks and after a period of approximately 14 days the  larvae are released. The veliger larva is will then spend some time in the water column before settling to the bottom where a new circular shell pattern is secreted and they transform into an olivoform (“bulla” stage). This juvenile stage possess a thin shell , which grows by addition of new shell material by the outer lip. Generally, the sex of the animal is related to shell size and female cowries have been shown to be larger than males in majority of species.

Size

Commonly 9 cm, but up to 16 cm.

Prey / Predation

They feed on sponges, bryozoans and algae, but have shown to feed on the flesh of fish and bivalves in captivity. Cowries have a radula, a tongue with which they can scrape off food.

Special features

Cowrie shells have been used as currency in the past in the Maldives, China, India, and East Africa. Nowadays, the shells are popular objects in the souvenir trade.