Ecological Risk Screening Summary - Ochmacanthus alternus (a catfish, 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.

Ochmacanthus alternus is a catfish native to the Negro and Orinoco River basins in the countries of Brazil and Venezuela in South America. It is a parasitic species, attaching to other fish and feeding on their mucus. Within the species native range, it has been observed that this method of feeding may cause avoidance behavior by the host and also loss of the host’s scales. However, there has been no documentation on invasiveness or introductions of O. alternus outside of its native range. Climate matching analysis showed that the subtropical temperatures of southern Florida were a medium climate match for O. alternus, but the contiguous United States had a low climate match overall. Overall risk assessment category for this species is uncertain.