Shipworm

Shipworms, teredo worms or simply teredo are a group of xylophagic marine bivalve molluscs in the family Teredinidae that consume wood submerged in saltwater. Their elongated, vermiform appearance makes their classification as bivalves not obvious, and sailors generally refer to them as "worms," a term found in the English shipworm and German Schiffsbohrwurm. However, taxonomically shipworms are more akin to clams. Shipworms are notorious for boring into (and eventually destroying) any wooden structure that is immersed in seawater, including piers, docks, and ships. Shipworms drill passages into wood by using their valves (shells) to rasp away and consume timber. They are sometimes called "termites of the sea". Carl Linnaeus assigned the common name Teredo (from Ancient Greek τερηδών (terēdṓn) 'wood-worm', via Latin terēdō) to the best-known genus of shipworms in the 10th edition of Systema Naturæ (1758). One species, Kuphus polythalamia, can reach over 1.6 m in length and 7 cm in diameter, making it one of the world's largest bivalves. This species consumes wood until it matures, after which it settles into marine sediment and relies on its symbiotic relationship with chemoautotrophic sulfur-eating bacteria for nutrition. Another species of shipworm, Lithoredo abatanica, burrows and feeds on carbonated limestone and lives in fresh water.