Fifth pereopod without an exopod
Hepatic carina straight, almost horizontal, distictly separated from base of antennal carina
Adrostral carina and groove extending as far as, or slightly ahead of apigastric tooth
Antennal carina very prominent, ending above middle of hepatic carina
Gastro-orbital carina extending over posterior half, or less of distance between hepatic spine and orbital margin
Petasma with distomedian projection slightly overhanging distal margin of costae
Ventral costae generally unarmed, sometimes minutely serrate at tip
Outer surface of lateral lobes generally unarmed
Inner surface of lateral lobes armed with spinules
Thelycum with lateral plates, their median margin sometimes forming tumid lips; anterior process concave rounded distally
Posterior process subtriangular, partly inserted between thelycal plates.
Fifth pereopod with small, but distinct exopod
Hepatic carina straight, sloping anterioventrally
Adrostral carina and groove extending beyond epigastric tooth
Antennal crest very prominent, ending above posterior third of hepatic carina
Petasma with distomedian projections reaching as far as costae
Free border of ventral costae unarmed or minutely serrate near apex
Outer surface of lateral lobes minutely tuberculate
Thelycum with lateral plates, their median margins forming tumid lips
Anterior process with raised edges delimiting a depressed area
Posterior process convex, partly inserted between lateral plates