Description of Alvinella pompejana
This species reported from hot hydrothermal vent habitats. Up to 13 centimetres (5 inches) long, pale grey with "hairy" backs; these "hairs" are formed by bacteria which are thought to afford the worm some degree of insulation. Glands on the worm's back secrete a mucus which the bacteria feed on. Also known as Pompeii worms, they form large aggregate colonies enclosed in delicate, paper-thin tubes. Pompeii worms get their name from the Roman city of Pompeii that was destroyed during an eruption of Mount Vesuvius in AD 79. Attaching themselves to black smokers, the worms have been found to thrive at temperatures of up to 80 degrees C (176 degrees F), making the Pompeii worm the most heat-tolerant complex animal known to science. They were first discovered at hydrothermal vents off the Galapagos. Thought to subsist on vent microbes, the Pompeii worm pokes its feather-like head out of its tube home to feed and breathe. The plume of tentacle-like structures on the head are gills, coloured red by haemoglobin. It is the posterior end that is exposed to extreme temperatures; the anterior end stays at a much more comfortable 22 degrees C (72 degrees F).