Chaetopterus

Chaetopterus or the parchment worm or parchment tube worm is a genus of marine polychaete worm that lives in a tube it constructs in sediments or attaches to a rocky or coral reef substrate. The common name arises from the parchment-like appearance of the tubes that house these worms. Parchment tube worms are filter feeders and spend their adult lives in their tubes, unless the tube is damaged or destroyed. They are planktonic in their juvenile forms, as is typical for polychaete annelids. Species include the recently discovered deep water Chaetopterus pugaporcinus and the well-studied Chaetopterus variopedatus.

==Housing tubes== The tubes the worms live in are either attached to rocks, or, more commonly, buried in sandy bottoms in shallow waters. The worm has spines along its body segments that are modified for tunneling into the sandy substrate to create the u-shaped tube within which it lives. The tubes are upright u-shaped tunnels lined with mucous, then the parchment tube, with the worm living inside the parchment tube. Each parchment tube ends with a chimney of parchment that juts above the substrate. The tubes can be as long as 85 centimeters and up to 4 centimeters in diameter at the widest portion in the buried central part of the tube. The chimneys may be wider or much narrower than the rest of the tube.