Sea urchin
Sea urchins or urchins () are typically spiny, globular animals, echinoderms in the class Echinoidea. About 950 species live on the seabed, inhabiting all oceans and depth zones from the intertidal to . Their tests (hard shells) are round and spiny, typically from across. Sea urchins move slowly, crawling with their tube feet, and sometimes pushing themselves with their spines. They feed primarily on algae but also eat slow-moving or sessile animals. Their predators include sea otters, starfish, wolf eels, and triggerfish.
Asthenosoma marisrubri
Asthenosoma marisrubri ('flexible body of the Red Sea') (Weinberg & De Ridder, 1998) aka Red Sea fire urchin and toxic leather sea urchin , is a relatively common sea urchin with a widespread distribution in the Indo-Pacific, and was till 1998 considered a color variant of "Asthenosoma varium". Sea urchins are close relatives of starfish, crinoids, brittle stars and sea cucumbers, all being echinoderms ('spiny skins').