Blepharipodidae is a

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

of sand crabs (

Hippoidea Hippoidea is a superfamily of decapod crustaceans known as mole crabs or sand crabs. Ecology Hippoids are adapted to burrowing into sandy beaches, a habit they share with raninid crabs, and the parallel evolution of the two groups is strikin ...

), comprising the two genera '' Blepharipoda'' and '' Lophomastix''. They are distinguished from the other families in the superfamily Hippoidea by the form of the

gill A gill () is a respiration organ, respiratory organ that many aquatic ecosystem, aquatic organisms use to extract dissolved oxygen from water and to excrete carbon dioxide. The gills of some species, such as hermit crabs, have adapted to allow r ...

s, which are trichobranchiate (filamentous) in Blepharipodidae, but phyllobranchiate (lamellar) in Albuneidae and Hippidae. Fossils belonging to the genus ''Lophomastix'' have been found in rocks dating back to the

Eocene The Eocene ( ) is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (Ma). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene'' comes ...

References

Hippoidea Decapod families {{Anomura-stub