A pale burrowing shrimp, known mostly from the mounds and open shafts it leaves on a slope.
A soft, pale, thin-shelled shrimp to about 8 cm, translucent white to pink with the gut visible as a dark line, the abdomen long and weakly built and one cheliped much larger than the other. The eyes are small and the body is not strengthened in the way a shrimp that lives in the open has to be, because the animal spends almost all of its life inside its own burrow.
The burrows are the part most divers see. A mud shrimp digs a deep branching shaft and pushes the spoil out at the surface, so the ground carries a conical mound of loose sediment with an open hole beside or on top of it, and on a productive slope there are dozens within a few metres. Water is pumped through the shaft with the abdominal appendages, and the sediment turned over in the process is enough to make the group one of the main agents reworking soft bottoms.
The animal itself appears at the mouth of the shaft, mostly at night, pushing sediment out before withdrawing again, and it is gone at any disturbance. Small crabs, shrimps, bivalves and worms are recorded living in the burrows alongside the builder. Records from a dive stay well above species level. Recorded from about 3 to 30 m.
Ratings are per location: 1 means found on most dives that look for it, 5 means a handful of records. Where enough dives have been logged the figure is calculated from them; otherwise it is an editorial estimate, and says so. We publish habitat and destination, not the dive site.