The Thermosbaenacea is a group of Peracarida that includes around a dozen species. Thermosbaena mirabilis is known from freshwater hot springs in North Africa, where the water may exceed 40 C. Several other species in this group live in much cooler fresh waters, typically in groundwater or caves. Still others are marine or inhabit underground anchialine pools (anchialine pools are landlocked bodies of brackish water with subterranean connections to the ocean; these unusual habitats are restricted to highly porous substrates, such as recently solidified molten rock or limestone adjacent to the sea). Limited data suggest that thermosbaenaceans feed on plant detritus.

(Brusca and Brusca 2003)