Paralvinella sulfincola

Paralvinella sulfincola, also known as the Sulfide worm, is a species of polychaete worm of the Alvinellidae family that thrives on undersea hot-water vents. It dwells within tubes in waters surrounding hydrothermal vents, in close proximity to super-heated fluids reaching over 300 °C (572 °F). The upper thermal limit for this polychaete is unknown; however, it is unlikely they can survive in constant temperatures over 50 °C (122 °F). It may tentatively be named a metazoan extremophile or, more specifically, a thermophile.

Their unique abilities to withstand high temperatures close to hydrothermal fluids enables them to prey upon sulphur-oxidising bacterial mats which grow close to the metal rich vent plume.