About Echinometra mathaei (Blainville, 1825)
Echinometra mathaei (Blainville, 1825) typically reaches a test diameter of approximately 5 centimetres (2.0 inches). Its overall colouration is quite variable, but the test itself is usually dark. Its spines may be green and purple with purple tips, or entirely green with purple tips. This species can be distinguished from other related sea urchins by a consistent characteristic pale ring located at the base of each spine. This species occurs on reefs in tropical regions of the Indo-Pacific Ocean, found at depths ranging down to 139 metres (456 feet). Its distribution range stretches from Madagascar, the East African coast, and the Red Sea all the way to Hawaii.
