discovered this wonderful creature in my tank,, hitchiker sila from my ne L.R.
http://www.youtube.com/watch?v=OuHNTWv0kVw (not my video)
info:
he sausage-shaped body of Bonellia viridis has a blue-green color and can reach a length of more than 15 cm. The body is buried in the substrate, and only the long, split "mouth" (proboscis) throat is visible, stretched out on the sea-floor. The proboscis is very extensible and may be stretched to ten times the body length. The mouth will contract swiftly into the body when the spoon worm is disturbed. Like other spoon worms, it feeds on deposits, but it has adopted an additional feeding strategy, as well. The skin contains a neural poison that can paralyze small animals.
http://www.seawater.no/fauna/echiura/viridis.html