Ecological Risk Screening Summary - Mexican Dwarf Crayfish (Cambarellus patzcuarensis) - Uncertain Risk

Species that are considered uncertain risk need a more in-depth assessment beyond the Risk Summary to better define the species’ risk to U.S. environments.

C. patzcuarensis is a freshwater crayfish native to Lake Patzcuaro, Mexico, and to springs in Chapultepec, Opopeo, and Tzurumutaro, Mexico. The species is widely available in the aquarium trade in Europe and North America, and is often one of the most commonly traded species. Authors from the Czech Republic reported a potential invasiveness (FI-ISK score) of 3 and a risk category (FI-ISK Category) of medium. Climate match with the contiguous United States is low, with southern California being the location of highest climate match for this species. Despite reports of extensive trade in recent years with no reports of establishment, the volume and duration of trade in C. patzcuarensis is not great enough to justify a low overall risk at present. Overall risk posed by Cambarellus patzcuarensis is uncertain.