Fire urchin

Scientific name : Asthenosoma varium

Large urchin with flattened, flexible test (the plates are articulated rather than fused). Very mobile, short spines, arranged in rectangular areas, separated by spineless areas. Spines have a blue swelling close to the tip, filled with venom. 25 cm.
Living in bay, lagoon, external reef; on sandy or rubble bottoms. The flexible test allows, changing the shape, to enter very narrow crevices. The swollen shape of the spines and the flexible test are unique features. The Red Sea species, once considered A. varium, has been recently re-named Asthenosoma marisrubri.
A. varium sting can be very painful, a strong local pain due to venom injection can last for hours.

Associated organisms
Often it hosts the commensal shrimps Allopontonia iaini, Periclimenes colemani and the parasitic gastropod Leutzenia asthenosomae.

	Description	Author	Place	Size
	Asthenosoma varium	DANIELE IOP	Indonesia, Lembeh strait	863 kB