Actinemys pallida, 134 - Tortoise and Freshwater Turtle Specialist Group

Distribution

Mexico, USA. The species occurs from northern Baja California, Mexico, north through the Coast Range to Monterey Bay, California, south of San Francisco, USA. The northern and southeastern boundaries are uncertain because turtles in the San Francisco Bay Area and along the southern edge of the Transverse Range in Los Angeles County have an admixture of both A. pallida and A. marmorata genes. Pure A. pallida occurs from the southern end of Monterey Bay south into Baja California, with disjunct populations in the westernmost Mojave Desert.

Estimated historical indigenous distribution of Actinemys pallida in California, USA, and Baja California, Mexico. Yellow dots = museum and current and historical occurrence records of presumed native populations based on literature and online records (TTWG 2025); orange dots = probable non-native introductions, translocations, or erroneous records; red dots = apparently extirpated populations; star = type locality. Colored shading = estimated historical indigenous range (dark red = extant; light red = apparently extirpated; purple = approximate area of partial hybridization with A. marmorata). Distribution is based on fine-scaled GIS-defined level 12 HUCs (hydrologic unit compartments) constructed around verified localities and then adding HUCs that connect known point localities in the same watershed or physiographic region, and similar habitats and elevations as verified HUCs, and further adjusted based on data from the literature and the authors. Map by Chelonian Research Foundation.

Citation

Germano, D.J., Bury, R.B., and Valdez-Villavicencio, J.H. 2026. Actinemys pallida (Seeliger 1945) – Southwestern Pond Turtle, Tortuga de Poza. In: Rhodin, A.G.J., Iverson, J.B., van Dijk, P.P., Stanford, C.B., Goode, E.V., Buhlmann, K.A., and Mittermeier, R.A. (Eds.). Conservation Biology of Freshwater Turtles and Tortoises: A Compilation Project of the IUCN SSC Tortoise and Freshwater Turtle Specialist Group. Chelonian Research Monographs 5(20):134.1–17. doi: 10.3854/crm.5.134.pallida.v1.2026; www.iucn-tftsg.org/cbftt/.

Author Information

¹Department of Biology, California State University at Bakersfield, Bakersfield, California 93311 USA [[email protected]]; ²1410 NW 12th Street, Corvallis, Oregon 97330 USA [[email protected]]; ³Conservación de Fauna del Noroeste, A.C., Jorge Mazón 291, Ampliación Punta Banda, Ensenada, Baja California 22897 Mexico [[email protected]]