''Lissodiadema'' is the only

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

in the family Lissodiadematidae.

References

Diadematoida Taxa named by Ole Theodor Jensen Mortensen {{Echinoidea-stub