chaetopterid polychaete Chaetopterus variopedatus

Chaetopterus variopedatus occurs worldwide, and in Antarctica has been found in the Weddell Sea, Antarctic Peninsula, Strait of Magellan, Cape Horn, Falkland Islands, Bouvet Island, and Kerguelen Islands from 1 - 585 meters depth [1,2 ].

Chaetopterid polychaetes are called parchment worms, and live inside a parchment-like tube they construct. Here's the worm found inside a tube. The Chaetopterus variopedatus worm is up to 25 centimeters long [2]. The worm's three disk-shaped parapods near its mid-section beat in a coordinated motion, pumping water through the tube [3]. The worm continuously secretes a mucus film, rolling it into a deep mesh-like bag through which the pumped water passes on its way through the tube [3]. Particles suspended in the water are retained by the mucus, and end up in a spherical mucus pellet in the mucus bag [3]. When this food ball is large enough, the worm stops pumping water and secreting mucus, and transports the food ball along a dorsal groove using cilia to its mouth for consumption [3].

1: Polychaeta Myzostomidae and Sedentaria of Antarctica. O Hartman. Washington D.C.: American Geophysical Union, National Academy of Sciences, National Research Council, 1966; 2: Polar Invertebrate Catalog, US National Museum, Smithsonian Institution; 3: Marine Biology 72(1):27-33, 1982

Text ©Peter Brueggeman. Photograph ©Paul Cziko. Photograph may not be used in any form without the express written permission of Paul Cziko.