What is "ice worm"

n. any of several worms, of the genus (taxlink Mesenchytraeus genus noshow=1), that inhabit glacial ice

Ice worms are annelids of the genus Mesenchytraeus. They are the only annelid worms known to spend their entire lives in glacial ice. They include M. solifugus, M. harrimani, M. kuril, M. maculatus and M. obscurus.

The first ice worms species were discovered in North America in 1887 in Alaska, on the Muir Glacier. These glacier ice worms can be found on glaciers in Alaska, Washington, Oregon and British Columbia. They have not been found in other glaciated regions of the world. The specific name solifugus is Latin for "sun-avoiding," as ice worms retreat underneath the ice before dawn. Enzymes in ice worms have very low optimal temperatures, and can be denatured at even a few degrees above . When ice worms are exposed to temperatures as modest as , their membrane structures disassociate and fall apart (i.e., "melt") causing the worm itself to "liquefy." Ice worms are several centimeters long, and can be black, blue, or white. They come to the surface of the glaciers in the evening and morning. On Suiattle Glacier in the North Cascades, population counts indicated over 7 billion ice worms.

Ice worms were described earlier by Evliyâ Çelebi in Turkey. "In 1648 Evliyâ observed these worms on Syna's Jebel-I Hayy' u's-selc, the 'Mountain of Hard Snow', and tells us that the snow gatherers presented them as gifts to physicians. Although the phenomenon had been described by many geographers and travelers since antiquity, it was dismissed by scientists as a myth until late nineteenth-century research proved that a species of dark brown or black worm (Mesenchytraeus solifugus) does indeed live in glaciers and permanent snow."

It is not known how ice worms tunnel through the ice. Some scientists believe they travel through microscopic fissures in ice sheets, while others believe they secrete some chemical which can melt ice by lowering its freezing point, like an antifreeze. They feed on snow algae.