Norman, 1869
Description
Generally resembling Diastylis rathkei but carapace of female smooth, with scattered hairs, of male with a smooth longitudinal carina on either side of which the front part forms an obtuse angle in its middle open towards the base and with pseudorostrum pointed, carrying two longitudinal series of spines decreasing in size from front to rear. Eye well developed.
Pereionite 5 of female serrated in front and deeply notched behind, with the lateral angles prolonged into a relatively short point, more produced in the male. Telson a little shorter than the uropod peduncles, its distal part, with 14-16 lateral spines, nearly twice as long as the proximal part. Basis of pereiopod 1 shorter than the ischium to propodus together, the propodus at least as long as the mews and carpus together and about twice as long as the dactyl.
Telson long, postanal part narrowed, with several pairs of lateral spines.
Remarks
According to Lagardère, 1971 the only reliable character separating this species from Diastylis bradyi is the much longer propodus of pereiopod 1 for any given carapace length.
Size
Length up to 11 mm.
Ecology
On muddy sand or mud.
Depth range
Between about 10 and 3000 m but usually on the shelf.
Distribution in the North Sea
Southern North Sea, Skagerrak.
World distribution
Recorded from the Skagerrak to the Ivory Coast, including the British Isles, but not in the Mediterranean.
[After Jones, 1976]