Girdle spicules under high magnification of Scanning Electron Microscope (SEM). Barents Sea, Arctic. © B. Sirenko.
Two images at different magnifications showing cuticle removed from flesh of girdle and opened flat so that the dorsal spicules (1), on perinotum, are at top, separated by a line of marginal spicules with ribs (2) from the ventral spicules (3), on hyponotum, below.
The spicules on the perinotum are small, c. 27µ long, widely spaced cones with sharp apices. Those on the hyponotum are longer, c. 35µ, more closely packed ovoids with longitudinal ribs.
The marginal spicules are straight, obtusely pointed and c. 48µ long. All are very difficult to discern with the naked eye.

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