Female: Head with no crest. P5 two-segmented. Rostral filaments separated into a basal and distal parts. The distal end of the lateral spine on P5 bent inward, abdomen shorter than the cephalothorax by slightly more than 2 times.
Male:
The left endopodite shorter than the exopodite by almost 2 times. The right endopodite reaches the distal end of the first segment of the exopodite.
North Atlantic, Scotland, Gascon Bay, Central Arctic
Oceanic, bathypelagic species. Usually found below 200m, but may be nearer the surface in the central Arctic and by night (interzonal migrants).
Females: Head low and not crested. Proximal end of rostral filaments separated from the distal end and much thinner. Last 2 thoracic segments separate, back corners of the last segment with angular short tips. A1 shorter than the cephalothorax. P5 two-segmented, the distal segment is swollen in the distal end and armed with 2 spines - a long apical spine and a short lateral spine - and with 1 serrated lateral chaeta. Sometimes a small spine is present at the base of the apical spine.
Males:
Rostral filament get thinner toward the end and do not have a separation between the distal and proximal parts. First segment of the exopodite of the right P5 with a large projection at the distal end, the penultimate segment of the same branch thin and curved, the distal segment significantly shorter than the previous one. The left exopodite short and stout, shorter in length than the endopodite by almost 2 times. The right endopodite is thin and sharp, one-segmented.
Females: 1,90-2,66 mm
Males: 1,90-3,40 mm
