Diadema setosum (Leske, 1778)
Porcupine sea urchin
photo by Batoy, Corazon B.

Family:  Diadematidae ()
Max. size: 
Environment:  reef-associated; marine; depth range 0 - 70 m
Distribution:  Indo-Pacific: from Red Sea to South Pacific Islands and Japan. Introduced in the Mediterranean.
Diagnosis:  Body is covered with long spines, with many shorter spines in between. Spines are black or dark purple, with the long ones often black-and-white banded, or white in color. Five bright white or blue spots are present on the test. The anal cone has a distinctive bright orange ring.
Biology:  Common in the sublittoral fringe around protected rocky coastlines (Ref. 102838). Found on muddy substrate (Ref. 2931). Occurs in assemblages in reef areas with high percentage of dead corals (Ref. 800). Common on Porites-dominated coral reefs; less common on Acropora assemblage (Ref. 102838). Feeds on algae (Also Ref. 128613) that grows on dead corals or rubble area (Ref. 800). Dwells in rocky and sandy substrates at depths of 1-70m. Also inhabits coral reefs and sea grass meadows. Hides in rocky crevices particularly when under intense light. Recorded from subsurface water temperatures of 16.9-30.8°C, oxygen concentration of 7.5 mg/L, and salinities of 36.4-38.7 per mille (Ref. 128613). Associated with coral communities. Dwells on soft substrates. Grazes on encrusting algae over hard substrates at night. Bioeroder. Keeps algal growth in check (Ref. 129602).
IUCN Red List Status: Not Evaluated (N.E.) Ref. 123251)
Threat to humans:  venomous
Country info:   
 

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