Females: Genital segment has a bump on the distal end on the left side. Two last abdominal segments densely plumose.
Males: Serrated plate on the last segment of the exopodite of the left P5 lacks serrations on the outer edge.
North Atlantic, Farer Canal, Azure and Canary Islands, Gibraltar, Gulf of Gascon, the central Arctic Basin, North Pacific, Kuril Islands
Oceanic, bathypelagic species; in the Arctic Ocean found at depths 0-1400m.
Females: Rostrum straight, relatively narrow and long, the back end of the thorax rounded and with dense pubescence. The genital segment has a protuberance only on the left side in the distal half of the segment at the base of the ventral crest. The genital field has oval shaped mounds, separated more toward the front. The genital segment is equal in length to the next two segment combined, the last segment and caudal rami densely plumose. The bare chaetae on the appendages are longer than the others. A1 as long as the cephalothorax. The outer spine on the second segment of the exopodite of P2 reaches above the next one, the middle spine is equal in length to half of the distance between its base and the base of the next spine.
The left P5 contains a plate serrated on the longer side, which narrows toward the distal end. Serrations are unequal in length. The penultimate segment has an elongated inner protuberance.
Egg-brooding species. Carry resistant sacs with a strong, highly visible membrane, which contain 10-20 large orange to bright red eggs. Eggs contain enough food stores for all the naupliar stages, and possibly the first 2 copepodite stages (which are presumed not to feed)
Females: 6.00-12.00 mm
Males: 6.10-10.00 mm
Active predators, feed on smaller copepods. Implements a sit-and-wait strategy, staying motionless in the water column, until prey comes into reach, then rapidly jumps towards the prey by movements of the thoracopods and the first antennae and catches the victim with the enlarged maxillipeds.