Cribrum is Latin for a sieve, and the name is a description of what the shell looks like: round white spots, all much the same size, spread evenly over a brown to orange ground, so that the shell appears to have been punched through with holes.
The animal that carries it is a different color again. Cowries wrap their shell in two flaps of mantle that rise from the foot and fold up over the back to meet along the middle, and here those flaps are bright orange with fine papillae over them. Alive on the reef this snail shows no shell at all, only orange tissue moving over rock, which is why divers who know cowries from a shelf often walk straight past them in the water.
That mantle is also what makes the shell what it is. It lays down new material from the outside as the animal grows, and it keeps the surface polished; a cowrie shell only loses its gloss once the animal is gone.
Under four centimeters (1.4 in), out after dark, under stones and deep in crevices through the day.
Linnaeus named it in 1758. Every one of the cowries in this batch carries his name and that date, which says something about the group: glossy, patterned, easy to collect, and therefore among the first sea animals in the world to get formal names.
- brown to orange shell with round white spots, evenly sized and evenly spread
- the spots read as holes punched through the shell, which is what the name means
- mantle bright orange, and it hides the shell completely
- under four centimeters
