Body more elongate than Pycnogonum littorale , almost cylindrical, anteriorly stouter, with lateral processes comparatively short and separated by wider intervals. Along the dorsal surface of the body extend a series of obtuse protuberances. Abdomen oval throughout, with the point evenly rounded off.
Ocular tubercle rounded, with comparatively large, closely set eyes. Proboscis pointing obliquely downwards, relatively short and thick, about one-third of the length of the body, conico-cylindrical, with the anterior end truncate, not produced.
Ovigerous legs in the male very small and feeble, having the first two segments larger than the rest, terminal claw slender and slightly curved. Ovigerous legs absent in female.
Ambulatory legs shorter than the body with a rough, granulous skin; femur and first tibia largest, about equal in length, each with the extremity above taking the form of two obtuse projections; tarsus more slender than in Pycnogonum littorale and regularly quadrangular; propodus slightly curved, scarcely at all tapering towards the extremity; terminal claw uncommonly powerful, more than half as long as the propodus, without an auxiliary claw.
Colour brownish or rusty. Length of the body in females, taken from the tip of the proboscis to the posterior end of the abdomen up to 10 mm. The males are generally somewhat smaller, up to 6.5 mm.
Found on coarse shelly sands in deeper waters.
A northern species.