Echinocardium
Echinocardium is a genus of sea urchins of the family Loveniidae, known as heart urchins. The name is derived from the Greek ἐχῖνος and καρδία.
Taxonomy
The genus was first described in 1825 by John Edward Gray, and the type species is Spatangus pusillus Leske, 1778 by subsequent designation.In 1836, the genus Amphidetus was described by Louis Agassiz, and is now considered a synonym of Echinocardium.