Spondylus squamosus   Schreibers,  1793 (Thorny oyster)
Organism information awaits expert curation
Class: Bivalvia

Size: Maximum shell height 10 cm, commonly to 8 cm.

Color: Outside of shell white to cream, with a few purple to blackish brown blotches on umbonal area and fine, concentrically interrupted, radial bands of similar colors on the interstices of the main ribs. Interior whitish, often tinged pale brown on ears and hinge. Internal margins marked with brown and purple on the crenulations.

Shell highly variable in shape but roughly rounded-ovate to elongate-ovate in outline, inequivalve. Right (lower) valve is somewhat more convex and higher than left (upper) valve, with a well-developed cardinal area. Attachment area ranges from moderately big to small, with a discrepant, mainly concentric sculpture. Outer surface of valves with low radial undulations forming a series of appressed, rather broad white ribs bearing generally a few short, flattened and often arched imbricate spines. Interstices of main ribs broad, radially ridged, sometimes with small and sharp fine spines. Main spinose ribs often slightly more numerous on right valve (8 to 12 ribs on right valve, instead of 5 to 8 on left valve). Hinge teeth of right valve more or less bifid on top. Internal margins with crenulations corresponding with the outer radial sculpture.

Synonym (s)
Spondylus ducalis Roding, 1798
Spondylus spathuliferus Lamarck, 1819
Spondylus japonicus Kuroda, 1932

Common Name (s)
Economic Importance and Threats
Importance:  Commercial
(Collected for food. Shell used for shellcraft.)

Habitat:  Reef Associated, Rocky



Literature Source(s)
  • Poutiers, JM (1998) Bivalves FAO species identification guide for fishery purposes. The living marine resources of the western central Pacific. Volume 1: Seaweeds, corals, bivalves and gastropods FAO, Rome 1 686 pp Available at - http://www.fao.org/docrep/009/w7191e/w7191e00.htm
  • Society for the Management of European Biodiversity Data (2009) World Register of Marine Species (WoRMS) Available at - http://www.marinespecies.org
  • Sharpe shells. The ocean's superstore Available at - www.specimenshells.net

Page last updated on:2010-06-09

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