Leach, 1814
Description
Rostrum upcurved, as long as or longer than carapace; ten to twelve dorsal teeth, normally four of these behind posterior edge of orbit; five or six (rarely seven) ventral teeth. Dorsal teeth do not extend into anterior half of rostrum.
Carapace with strong antennal spine and small pterygostomian spine.
Stylocerite broadly rounded, shorter than eye. Apical spine of scaphocerite exceeds lamellar portion. Third maxilliped 0.83 x length of scaphocerite; epipod present.
Pereiopod 1-4 with epipods and arthrobranchs, pereiopod 5 with setobranch. Pereiopod 1 minutely chelate. Second pereiopods asymmetrical: pereiopod 2 right: carpus of 20-22 segments, merus occasionally with indistinct annulations at distal end; pereiopod 2 left: carpus of 50-65 segments
Mandible with molar and incisor processes, and three-segmented palp with lateral lobe on proximal segment.
Telson with five to seven pairs of lateral spines.
Remarks
This species is a protandrous hermaphrodite, males usually developing female characters after thirteen to sixteen months.
Some difficulty may be experienced in counting the segments of the carpus of pereiopod 2, since they tend to become less distinct proximally.
Size
Length up to 160 mm, but normally less than 100 mm.
Colour
Usually semi-translucent, with red chromatophores giving overall pink colour.
Carapace often with oblique red lines, these lines becoming more horizontal on pleonites.
Ecology
Occurs on gravelly, sandy and muddy substrates. Hyperbenthic species, may swim up at night, mostly confined to the nepheloid layer; adults may get caught with pelagic sampling.
Ovigerous females from November to April-May.
Depth range
Down to about LWS-230 m, but rarely over 100 m.
Distribution in the North Sea
All North Sea, maybe less common in the south; larvae reported from CPR areas B2 and C2 CPR/NorthSea .
World distribution
Ranges from W Greenland, Iceland, Faeroes, Norway and Britain south to 50°N. In W Atlantic, ranges from 41°N to 65°N. Also known from north-east Pactfic, 39°N to 65°N.
[After Smaldon, 1993]