(Krøyer, 1841)
Description
Body slender and elongate. Pseudorostrum a little upturned in female, nearly horizontal in male, obliquely truncate and setiferous in female with a deep antennal notch and acute anterolateral angle below; in male the lobes are shorter, almost transversely truncate, with the antennal notch scarcely excavated and the anterolateral angle rounded and barely prominent.
In the female the mid-dorsal crest is serrate from behind the pseudorostrum to beyond the middle and after an interval again serrate to the hind margin; in the adult male there are no serrations.
Peduncle of antenna 1 without a marked geniculation. Antenna 2 of female with a well-defined distal segment. Pereiopod 3 of adult male with two conspicuous unequal ensiform setae on the ischium extending twice as far as the rest of the appendage (discounting the setae or spines on the carpus, propodus and dactyl). All the pereion segments are visible from above.
Pleopods without an external process on the inner ramus, two pairs, rarely one or none, in male. Exopodites present on the third maxillipeds and on the first four pairs of pereiopods, rarely the first two pairs, in the male; in the female on the first three pairs, rarely the first two pairs.
The mandibles are broadened at the base. The peduncle of the uropods is as long as the rami; the distal segment of the endopod is less than half as long as the proximal. The endopod of the uropod is two-segmented or rarely one-segmented. No free telson.
Depth range
Probably widespread on muddy bottoms, usually in moderate depths between 10 and 100 m, but found down to more than 500 m.
Size
Length of male up to 10 mm, of female up to 12 mm.
Depth range
Distribution in the North Sea
Northern North Sea, Skagerrak.
World distribution
An Arctic-Boreal species, recorded on both sides of the Atlantic in colder water and extending into the Arctic and also from Alaska.
[After Jones, 1976]