Apatopygidae is a family of
echinoderms
An echinoderm () is any animal of the phylum Echinodermata (), which includes starfish, brittle stars, sea urchins, sand dollars and sea cucumbers, as well as the sessile sea lilies or "stone lilies". While bilaterally symmetrical as larv ...
belonging to the order
Cassiduloida
Cassiduloida is an order of sea urchins. The group was extremely diverse with many families and species during the Mesozoic
The Mesozoic Era is the Era (geology), era of Earth's Geologic time scale, geological history, lasting from about , com ...
.
Genera:
* ''
Apatopygus''
Hawkins, 1920
* ''
Jolyclypus''
Lambert, 1918
* ''
Nucleopygus''
L.Agassiz, 1840
* ''
Porterpygus''
Baker, 1983
References
Cassiduloida
Echinoderm families
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