Rigid Cushion Star
Body with a large disc and 5 small, narrow and tapering arms; R/r: 2; up to 400 mm in diameter, but usually smaller. Coloured red.
The plates on the upper surface are of various sizes. The larger plates bear a thick spine or a pedicellaria in the middle and a series of graines around the edge. The smaller plates are disposed irregularly around the larger ones. The marginal plates each bear 1-3 thick spines in the middle and a series of grains along the edges.
The oral interradial area is very large, with numerous large pedicellariae (p), each surrounded by a circle of grains (g). Along the ambulacral furrow the pedicellariae are arranged in a fairly regular longitudinal series, each pedicellariae standing obliquely to the furrow (H. phrygiana pedicellaria).
This species is found on various substrata, from 20 m down to depths of about 800 m.
In the North Sea it is found from the Shetland Islands down to Northumberland on the British east coast. Elsewhere it is northerly distributed from Scotland to Greenland, Iceland and Finmark.