Carapace transversely oval, smooth with regions not well defined, H-shaped grove in centre and without setae. Frontal region without medial fissure. Anterolateral margin is convex divided by shallow depression into four lobes. A small gap is present on the internal margin of the eye allowing the flagellum of the antenna to enter the orbit. Chelipeds markedly unequal, one strong crushing claw and the minor chela is slender with long fingers. Walking legs are laterally compressed with setal mats on the distal portion of the propodus and entirely covering the propodus. All male abdominal somites are moveable.
Vernacular name: Pebble peeler.
These crabs occur in the upper tidal zone hiding under rocks and pebbles. One of their claws is specially modified to cut open snails while the other has long thin fingers to pull out the exposed flesh.