Mole Crab Family, (Hippidae): The Hippidae family of Mole Crabs is comprised of Emerita Genus and the Hippa Genus. Members of the Emerita Genus have a strongly convex oval shell or carapace that covers the legs, front legs without claws (nonchelated) and back legs (telson) that resemble paddles, long slender antenna and long slender eye stalks.
Members of the Hippa Genus have a similar carapace, but front (nonchelated) and back legs that are slender and pointed, short stubby antenna and short stubby eye stalks. The Mole Crabs reside buried in sifting sand on wave-swept beaches in areas washed by waves.
They bury themselves near the surface, facing seaward, with only their antennae and eyes out of the sand. They collect floating debris from waves draining off the beach with their first pair of legs transfer food to their mouths, They adapt to conditions of heavy surf and strong currents. In some places they are fairly abundant but difficult to observe because they blend into the background extremely well.
Interestingly they reproduce based on food availability and not on tidal or water temperature changes. There are four mole crabs found in Mexican waters, known as Muy-muy Cochitos. They are a favorite live bait of the Southern California surf fisherman but not utilized often as bait in Mexico.