root › cellular organisms › Eukaryota › Opisthokonta › Metazoa › Eumetazoa › Bilateria › Deuterostomia › Echinodermata › Eleutherozoa › Echinozoa › Echinoidea › Euechinoidea › Acroechinoidea › Diadematoida › Diadematidae › Diadema › Diadema antillarum