Flame File Shell - Lima

Photograph by Roger Steene

The file shell, approximately 40 mm long, can be a startling find under coral rocks and boulders because, unlike most bivalves, it can move very rapidly when disturbed, swimming off in a series of jerks by rapidly opening and shutting the valves of its shell to force out a jet of water. The mantle is bright red, and around the edge are long, sticky, retractile tentacles, which continuously wave around. When touched, the tentacles stick to whatever touches them, and they often break off. They are probably, defensive, confusing fishes by sticking to their mouths and waving about, while the shell rapidly jerks away.

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