Schizobranchia insignis is a marine Feather Duster Worm.

Description

Tube is 10-20 cm long, 5-10 mm in diameter, whitish and pliable. Color of tentacular crown is uniform orange, red, mauve, tan, brown, grey, or green.

Habitat

Commonly found living attached to pilings and rocks, intertidal to 46 m. Abundant on the underside of wharves in Puget Sound. Can be found on wharves at Boston Harbor marina.

Life History

Schizobranchia insignis is free-spawning, releasing gametes into the water column for fertilization. If disturbed by touch, water movement, or shadow, the tentacular crown can be quickly withdrawn entirely within the tube, by retractor muscles. Ciliated radiole

Radiole

A radiole is a heavily ciliated feather-like tentacle found in highly organized clusters on the crowns of Canalipalpata. Canalipalpata is an order of sessile marine polychaete worms consisting of 31 families...

s (feathery tentacles) collect planktonic particles, which are trapped in mucus and carried to the mouth.

Physiology and Biochemistry

Schizobranchia insignis has been found to accumulate dissolved carbon exuded by an alga. For feeding and respiration, S. insignis reportedly passes 70 ml/hr/g animal (fresh weight) of water through the tentacular crown by the cilia's movement. The hooked setae of Schizobranchia insignis have been found to dig into the tube wall and serve as anchors, likely to secure the worm from being sucked out by a fish or pulled by wave action. Worms were found to withstand high pressures of 100-200 kPa (applied experimentally, from posterior).

Ecosystem Role

Along with other species of polychaete worms, S. insignis is host to kleptoparasitic suspension-feeding snails, like Trichotropis cancellata, that live on the worms and steal food.

Identification

Among Pacific Northwest sabellids, S. insignis is unique in that all radioles are dichotomously branched at least once. Radioles of Eudistylia polymorpha are not branched, and only a few of the radioles of E. vancouveri are branched.

External links

• photo of S. insignis (Intertidal Marine Invertebrates of the South Puget Sound)
• photo of S. insignis (California Academy of Sciences)