Ecological Risk Screening Summary - Cherax rhynchotus (a crayfish, no common name) - 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. This additional information will help inform decisions on where, when, and how the species may be used to minimize risks of them becoming invasive.

Cherax rhynchotus is a crayfish native to tropical northeast Queensland, Australia. It may also be native to southwestern Papua New Guinea, but most sources do not report the species distribution as extending to that country. There is also taxonomic uncertainty about the validity of the species, after molecular genetics work showed no discernable difference between C. rhynchotus, C. bicarinatus and C. barretti. No introductions of the species have been reported so impacts of introduction remain unknown, although the possibility of impacts has led Florida and Washington to prohibit the possession, trade, and transport of the species. C. rhynchotus has a low climate match to the contiguous U.S. Overall risk assessment is uncertain.