Carapace sub-rhomboidal in lateral view, with a blunt caudal process above mid-height and rounded, truncate alae terminating well behind mid-length. Posteroventral margin compressed. Greatest width a little behind mid-length. Ornamented with vertically elongate fossae in the posterior half, giving way anteriorly to more rounded, scattered fossae.
Sublittoral species found on a variety of substrates all around the British Isles in water depths of 5-80 metres.
Norman published identical type descriptions in two separate publications in 1865; only in one was the species illustrated.
It occurs between latitudes 50° and 70° N in NW Europe.