A thorny oyster (Spondylus varius: 18 cms.). Notwithstanding its common name, this species is more closely related to scallops than to oysters. It cements itself firmly to a rocky part of the coral reef where - like most bivalve molluscs - it uses filter-feeding to catch plankton. It opens and closes its shell by means of powerful muscles operating a ball-and-socket mechanism. It closes promptly when alarmed but, if one waits, will open. It has a well-developed middle mantle and sensory tentacles together with multiple eyes around the shell margins. Photographed in Balinese waters, Indonesia.

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Size: 4572px × 3044px
Location: Tulamben, Bali, Indonesia
Photo credit: © Terence Dormer / Alamy / Afripics
License: Royalty Free
Model Released: No

Keywords: adventure, bali, bivalve, coral, creation, diving, eyes, indonesia, mollusk, multiple, natural, oyster, picture, reef, scallop, scuba, selection, spiny, spondylus, thorny, trd5143, underwater, varius