Red Sea Fire Urchin, Asthenosoma marisrubri
The Red Sea Fire Urchin or Toxic Leather Sea Urchin (Asthenosoma marisrubri) is a relatively common sea urchin with a widespread distribution within the Indo-Pacific, and was, until 1998, considered a color variant of Asthenosoma Varium. Sea urchins are close relatives are crinoids, brittle stars, sea cucumbers, and starfish, all being echinoderms.
This species grows to 25 centimeters in diameter, with articulated plates making the test quite flexible. It prefers water temperatures between 24 and 27 degrees Celsius and depths down to 90 meters. It survives on a wide variety of food including algae, bottom detritus and coral polyps. It’s most active during the night and is named for the extreme pain inflicted by its spines and its occurrence within the Red Sea.