Hydnophora exesa (Pallas, 1766)
Hydnophora exesa
photo by Veron, Charlie (J.E.N.)

Family:  Merulinidae ()
Max. size: 
Environment:  reef-associated; marine; depth range 0 - 40 m
Distribution:  Indo-Pacific.
Diagnosis:  More recognizable when polyps are retracted. Characterized by conical collines called monticules, which sometimes combine to form ridges. Color varies from grey to blue or bright green.
Biology:  Occur in small colonies. Polyps expand during the day. An extremely aggressive species. Surface is often covered with barnacles, particulary Creusia spp. (Ref. 130769).
IUCN Red List Status: Near Threatened (NT); Date assessed: 03 January 2008 Ref. 123251)
Threat to humans: 
Country info:  Known from Cape D'Aguilar (Ref. 124794) and Hoi Ha Wan (Ref. 127094). Also known from Sharp Island, Bluff Island, and Long Ke Wan (Ref. 125433). Usually occur in small colonies (Ref. 130769). C: Refs. 121111, 124794, 125433, 127094, 130769; M: Ref. 121111.

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