Can be easily distinguished by the structure of the rostrum and long caudal setae, which are longer than the abdomen
Atlantic species, sometimes extends its range into the Arctic region
Oceanic, epi- to bathypelagic species
Female:
Rostrum is directed anterioventrally, is visible from dorsal view. Caudal setae are longer than the abdomen. Eggs inside egg-sac are usually placed in 2 rows.
Male:
Rostrum is absent. Both A1 are geniculate. The caudal setae are significantly shorter than in female.
