To see a great picture of Eudistylia polymorpha go to http://www.oceanlight.com/html/bryozoans_tunicates_hydroids_w.html.
or to this site http://www.sanctuaries.nos.noaa.gov/pgallery/pgchannel/living/living_12.html
US Federal List: no special status
E. polymorpha has adapted its habitat to fit wharves, harbors, and floats along the Pacific Coast. The worms' habit of adhering to these man-made structures could be bothersome to marine workers. These worms are also considerably hard to remove, anchoring deep in crevices of their substrate; it has been thought that "one might need the help of a crow bar to pry the enitre animal from its ground." (Snook and Johnson, 1967)
E. Polymorpha is a special delight to scuba divers and snorkelers of the Pacific Coast. This is also an easy species to dissect to learn more about the Phylun Annelida. This worm has a few variations from the regular segmented worms that may make it interesting to those studing invertebrate anatomy. (Fox, 1994)
E. polymorpha is a member of the family Sabellidae which are suspension feeding polychaetes. These animals are active suspension feeders in that they create a current to direct food particles. Their location in moving water is vital to their survival because the current must bring a continous flow of food particles.
The network used to direct these food particles begins with spiral bundles of pinnately branched, ciliated branchiaeon arising in a row around the branchial stalk. These are located on each side of the head. Posterior to the two branchial stalks is a large funnel-like mouth. The branchiae groove is responsible for transporting food to the mouth in that it leads to a large stalk groove that spirals down the brachial stalk and empties into the mouth.
Food collected by the meshwork of ciliated pinnules is sorted and transported to the mouth by this system of grooves. These pinnules have a groove on their medial surface with two types of cilia that further aid in capturing food by creating a feeding current. These cilia also lead food to the branchial groove on the branchial axis.
In the digestive system of the E. polymorpha, a gut tube which fills most of the space in the coelem, includes the mouth and anus. Its epithelium is ciliated. The stomach epithelium is ciliated and has secretory cells, but the intestine lacks these. (Fox, 1994)
E. polymorpha can been spotted all along the Pacific Coast from Alaska to San Pedro. It is especially common in the Pacific Grove. (Ricketts, et al 1985)
Biogeographic Regions: pacific ocean (Native )
E. polymorpha lives in its translucent greyish, tannish tube that is attached to rocks, pilings, harbors, floats, and wharves along the Pacific coast. This tube is often encrusted with bits of shell or sand. They anchor the tubes deep into the rocks to prevent "uprooting" and it is known to take a great deal of effort to pry an entire animal froms its location. Some have even been found anchored in sponges.
They may be found near the low-tide line to water 1400 feet deep. However, more often they inhabit tide pools in large numbers giving the appearance of a flower garden. (Snook and Johnson, 1967; McConnaughey and McConnaughey, 1986)
Aquatic Biomes: coastal
The Giant Feather Duster Worm is usually 10" long and about 1/2" wide. The body of E. polymorpha is encased in a translucent, tannish tube which is often encrusted with sand and bits of shell. Its large plume of 30 feather like gills on each side of the tube is 2 1/2" across when expanded. They may be maroon, reddish, orange, or brown and usually have cross bands of lighter and darker shades. The gills have numerous eyespots which aid them in sensing when to retract into their tubes.
There are two key characteristics in distinguishing E. polymorpha from E. vancoveri, a very similiar organism and possible hybridizing partner. The dorsal edge of the the branchial crown of E. polymorpha is deeply cleft, and the gills are usually deep maroon with orange tips. On E. vancoveri the gills are red with white tips and the crown has no cleft. (Snook and Johnson, 1967; Ricketts, et al 1985; McConnaughey and McConnaughey 1986)
Other Physical Features: ectothermic ; bilateral symmetry
Fertilization is external. The anatomy of the reproductive system includes gonads that are in back of the abdomen, bulging into the anterior part of the coelomic compartments, and two ciliated gonoducts which exit the coelom of each segment and open ventrally via gonopores near the abdominal fecal groove. Gametes accumulate in the coelomic spaces of the abdomen where they mature.
When mature, gametes enter the gonoducts, leave via the gonopores and are carried forward by cilia of the fecal groove. Palps with cilia, next to the first branch of each brachial stalk, transport gametes from the fecal groove to be released into the sea.
Sperm receptacles are known to occur at the base of crown tentacles in females of three species. In addition, free spawning also occurs in which individuals produce oocytes 140-200 um in diameter. (Brooding species produce oocytes over 200 um in diameter.) These are deposited in gelatinous masses on the tube or on sediment surface and are retained in a membraneous capsule tube.
Development to non-feeding pelagic trochophores and setigerous (segmented) larva is rapid. Settlement occurs in three to four weeks.
Many individuals have been found with characteristics of both E. polymorpha and E. vancoveri, implying that hybridization between the two species may occur.
(Fox 1994; Strathmann, 1987)
Eudistylia polymorpha, the giant feather duster worm, is a species of marine polychaete worm belonging to the family Sabellidae. Its common name is from the crown of tentacles extended when the animal is under water.
E. polymorpha has a body up to 25 cm (10 in) long and 1.2 cm (0.5 in) thick and lives within a tube. This is parchment-like and composed of sediment cemented with mucus. It is a brownish colour, translucent and often strengthened with sand and shell fragments. On rocky shores, it may be hidden in a crevice and difficult to dislodge. The branchiae (feeding appendages) in the feathery crown also function as gills. They are also known as radioles, and are a shade of red or brown, banded with paler sections. Shades vary, but the most frequent colouration is maroon with orange tips. They arise from two spiral, deeply cleft, bases.[2] They bear eyespots which alert them to sudden shadows or movements nearby. This enables the crown to be retracted into the tube very rapidly when danger threatens. The posterior segments of the worm bear hooked bristles which help anchor it in its tube.[3] E. polymorpha can be distinguished from the very similar Eudistylia vancoveri by the cleft in the crown. Also, E. vancoveri generally has red branchiae with white tips.[4]
The range of E. polymorpha extends along the western coast of North America, from Alaska to California. It is found in the intertidal zone in tide pools and in the neritic zone at depths up to 420 m.[5] It tends to grow in groups and can be found growing on rocks, reefs, pilings, wharves and marinas.[6]
E. polymorpha is a filter feeder, catching food particles with its pinnately branched radioles. It prefers to live in moving water so a constant stream of particles comes within reach. These are trapped by the feeding appendages and moved by cilia down grooves in the radioles to the large, funnel-shaped mouth. The gut takes up most of the coelom space and there is a faecal groove for ejection of undigested debris.[4] Any particles too large to be ingested get incorporated into the tube structure.[3]
Reproduction takes place in the spring, and fertilization is external. The gonads are on the dorsal side of the abdomen and the gametes mature in the coelomic spaces. They are then passed forward by cilia along the faecal groove and are released into the water column. The larvae are planktonic and grow rapidly. After about three or four weeks, they settle out as segmented larvae.[4]
Eudistylia polymorpha, the giant feather duster worm, is a species of marine polychaete worm belonging to the family Sabellidae. Its common name is from the crown of tentacles extended when the animal is under water.
