Thermosphaeroma thermophilum, commonly known as the Socorro isopod or Socorro sowbug, is a crustacean in the family Sphaeromatidae. It was endemic to the thermal water of Sedillo Spring located in Socorro County in the state of New Mexico, United States.
In the isopod's natural habitat the thermal waters ranged in temperature from 26–33 °C (79–91 °F). In 1947, when the spring was diverted to supply the city of Socorro with drinking water, the isopod ended up living in an old water supply pipe that led to a horse trough and two small, old, concrete bathing pools. In 1988, the wild population became extinct, when a tree root burst the pipe and cut off water flow to the concrete pools. Existing captive populations were bred to restore the isopod community near the spring and they were reintroduced, into eight new concrete pools (tanks). As of 2006, captive populations are kept at the Albuquerque Biological Park, the Minnesota Zoo, the New Mexico Department of Game and Fish Laboratory in Santa Fe, and by the Department of Biology at New Mexico Tech.
- Inland Water Crustacean Specialist Group (1996). "Thermosphaeroma thermophilum". IUCN Red List of Threatened Species. Version 2009.2. International Union for Conservation of Nature. Retrieved April 1, 2010.
- Charles C. Mann & Mark Plummer (1995). "Is Endangered Species Act in danger?". Science 267 (5202): 1256–1258. doi:10.1126/science.267.5202.1256. PMID 17812587.
- Leslie Ann Mertz (2004). "Isopoda (pillbugs, slaters, and woodlice)". In Michael Hutchins et al.. Grzimek's Animal Life Encyclopedia: Volume 2: Protostomes (2nd edition ed.). Detroit, Michigan: Gale. pp. 249–260. ISBN 0-7876-5778-6.
- New Mexico Department of Game and Fish (August 25, 2006). "Threatened and Endangered Species of New Mexico: Biennial Review and Recommendations" (PDF).
- Veijo Jormalainen & Stephen M. Shuster (1997). "Microhabitat segregation and cannibalism in an endangered freshwater isopod, Thermosphaeroma thermophilum" (PDF). Oecologia 111 (2): 271–279. doi:10.1007/s004420050235.