Parchment worm

Others polychaetes are considered to be sedentary because they stay in one place, waiting for food to come to them. Their bodies are often shorter than errant worms, with clearly defined regions. Like the sabellid worm in the lower color insert on page C-2, sedentary polychaetes spend their lives in tubes or holes and have developed a variety of special adaptations for feeding and breathing in these niches. Most of these worms consume plankton or other small material that is suspended in the water. Some species of sedentary polychaetes include the coiled tube worm, sand builder worm, trumpet worm, parchment worm, lugworm, and hard tube worm. 

This bizarre-looking worm lives in a U-shaped parchment-like tube up to 25 cm long (Fig. 7.1.1), which is usually buried in sand or mud, exposing only the openings of both ends. It is a filter feeder, and very widely distributed, sometimes forming dense colonies on the seabed. In fact, this species propagated so densely in the Los Angeles Flarbor around 1965, Dr. Rimmon Fay was able to collect 10,000... 

Fig. 7.1.1 Left Two parchment-like tubes inhabited by Chaetopterus variopedatus. The tubes are usually buried in muddy sand, exposing only the openings at both ends. Center The worms after removal of the casings. Right Diagram showing luminous area (after Panceri, 1878) the third pair from the top corresponds to the 12th segment.

Segmented worms are generally found along the bottom, living in deposits of sediment or under rocks. Some types build tubular homes for themselves in which they spend their entire lives. These sedentary worms include the parchment tube worm and the trumpet tube worm. Errant species, such as bloodworms and syllid worms, spend some of their time out of their hiding places, actively seeking prey. 

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