SEA STARS OF THE PACIFIC NORTHWEST WRINKLED STAR Pteraster militaris

Class Asteroidea

Order Velatida

Family Pterasteridae

WRINKLED STAR

Pteraster militaris (O. F. Müller, 1776)

Identification:

5 (rarely 6 or even 7) short, puffy, heavily wrinkled arms and disc with a large central pore. Aboral surface soft to the touch. Pale yellow to pink. To 15 cm (6 in) across.

Range:

Arctic circumboreal. In the north Pacific, from the Bering Sea to California; 10 to 1,100 m (33 to 3,609 ft).

A typical WRINKLED STAR. Note the stubby, heavily wrinkled arms and large central pore.

A puffy WRINKLED STAR feeds on a WHITE RETICULATED SPONGE.

This specimen is feeding on ENCRUSTING HYDROCORAL Stylantheca papillosa.

An unusual 6-armed specimen.

A specimen at Skookumchuck Narrows, BC, where they are fairly common.

Another specimen from Skookumchuck Narrows, BC.

3 - 6

Notes:

Prey include CLOUD SPONGES Aphrocallistes vastus, WHITE RETICULATED SPONGE Iophon lamella as well as the HYDROCORALS Stylaster verrillii and Stylantheca papillosa.

This star has a large dorsal chamber under the aboral skin. Females retain some of their eggs in this chamber and once fertilized, 30 to 40 juveniles grow to about 1 cm (0.4 in) across before exiting through the dorsal pore.