There are usually 5 to 9 teeth on each anterolateral margin, and the posterolateral margins usually converge . The endopodite of the second maxillipeds has a strongly developed lobe on the inner margin. The legs are laterally flattened to varying degrees and the last 2 segments of the last pair of legs are paddle-like. The male’s abdominal segments 3 to 5 are completely fused and immovable.