Children (7 direct children, 260 direct and indirect children):
Loveniidae
(tree size 64)
Spatangidae
(tree size 33)
Eurypatagidae
(tree size 22)
Macropneustidae
(tree size 29)
Maretiidae
(tree size 53)
Eupatagidae
(tree size 46)
Eupatangidae
Megapneustidae
(tree size 6)