Order

Venerida

  Class

Bivalvia

  No. of Genera in Ref.

  No. of Species in Ref.

  Environment

Fresh : No | Brackish : No | Marine : Yes

  Aquarium

  First Fossil Record

     

  Remark

Shell usually thick and irregularly rounded in outline, strongly inequivalve and inequilateral; very variable in shape, often distorted, cemented to the substrate by either the left or the right valve; cemented, lower valve larger and deeper than the more or less flattened upper valve. Umbones prosogyrate, low, spirally wound. Sculpture usually well developed, concentric or radial or both, frequently leaf-like to spinose. Periostracum inconspicuous. Ligament external, in a groove of posterodorsal margin. Hinge thick and arched, with large curved teeth and corresponding sockets, more or less parallel to dorsal margin. Interior of shell porcelaneous. Two large subequal, ovate and dorsoventrally elongate adductor muscles scars. Pallial line without a sinus. Internal margins often denticulate. Gills of eulamellibranchiate type, with folded branchial sheets; outer demibranch smaller than the inner and dorsally expanded. Mantle margins papillated, open anteroventrally, fused and forming 2 short siphons posteriorly. Sedentary animals, common in coral reefs and rocky shores, living strongly cemented by one valve to the substrate. Suspension filter feeders. Sexes separate. Fertilization external, eggs hatching as free-swimming planktonic larvae. Chamidae are locally collected for subsistence. Their shell may be used as lime material, and in some areas (when not heavily eroded or encrusted by marine growths) to make decorative items or sold for shell collections (Ref. 348).

  Etymology

  Division

  Reproductive guild

  Typical activity level

  Main Ref.

  Coordinator