Page 77 - Caribbean Reef Life Demo

ATLANTIC THORNY OYSTER (Spondylus americanus) < 15 cm / 6 in Rounded deep red shell with numerous pointed spines on both top and bottom. Brown mantle with white blotches.
Oysters remain attached to the reef, while clams and scallops are able to swim about. This family of bivalves has been on Earth since the early urassic period. The Atlantic Thorny Oyster above can snap shut when threatened. It has a total of 1 3 tiny eyes lining its mantle. Oysters can be either male or female, and reproduce in the late summer by broadcast spawning; each oyster on the reef throws out millions of eggs or sperm into the water. Each species will time their release for the best chance that the eggs will become fertilized and eventually settle on a new patch of reef.
Oysters live by ltering seawater for their food and minerals. They can live for decades. As they slowly grow they will usually be covered in encrusting sponges and other marine life. Often only the shell opening and a small part of the interior mantle is visible to divers.
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