Arca ventricosa Lamarck, 1819
Ventricose ark
Arca ventricosa
photo by Batoy, Corazon B.

Family:  Arcidae ()
Max. size:  9 cm TL (male/unsexed)
Environment:  benthic; marine; depth range 0 - 20 m
Distribution:  Indo-Pacific: East Africa to Red Sea and Polynesia.
Diagnosis:  Shell equivalve, thick and inflated, very inequilateral, posteriorly expanded. Shape somewhat irregular, elongate rectangular in outline, with strongly protruding umbones anteriorly and a broad rounded keel from umbones to posteroventral margin. Posterior margin obliquely truncate, ventral margin slightly sinuous with a well-developed byssal gape. Cardinal area wide and riblets crossed by irregular growth marks, and a few larger radial ribs on posterodorsal slope. Periostracum coarsely pilose, mainly persisting towards shell margins. Hinge straight very long and narrow. Internal margins smooth. Colour: Outside of shell often encrusted with marine growths; posterior half dark brown, anterior half creamy white with zebra-like brown stripes. Inner side more or less strongly tinged with dark brown.
Biology: 
IUCN Red List Status: Not Evaluated (N.E.) Ref. 123251)
Threat to humans:  harmless
Country info:   
 

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