The Micropygidae form a family of

sea urchins Sea urchins or urchins () are echinoderms in the class Echinoidea. About 950 species live on the seabed, inhabiting all oceans and depth zones from the intertidal zone to deep seas of . They typically have a globular body covered by a spiny p ...

within the Diadematoida order of echinoderms. The family contains two living species of the genus ''Micropyga'' and one, ''Kierechinus'', known only from

fossils A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

. Morphologically, they are quite flat and have short, sharp spines, which are close to each other. They occur in the Indian and Pacific Oceans.

References

Diadematoida Echinoderm families {{Echinoidea-stub