Ecological Risk Screening Summary - Red-rim Melania (Melanoides tuberculatus) - High Risk

Species that are considered high risk have a well-documented history of invasiveness in at least one location globally, and a high or medium climate match to the contiguous United States.

Melanoides tuberculata, red-rimmed melania, is a mollusk that is native to much of Africa and southern Asia. The species has become established in North and South America, Europe, and Oceania, primarily through the aquarium trade and intentional introduction as biocontrol for the native snail hosts of trematodes that can cause schistosomiasis. In the United States, M. tuberculata is established along the Gulf Coast from Florida to Texas, in California, and in warm springs in the Interior West. Transport, possession, sale, stocking, or cultivation of M. tuberculata is regulated by at least five U.S. States. M. tuberculata has been responsible for declines in native snail populations in multiple locations in the Caribbean and Central America. The species is also a host for numerous parasites of significance to humans and other animals, including an endangered fish species. The History of Invasiveness for M. tuberculata is classified as High due to its successful establishment outside its native range and the clear, convincing, and reliable documentation of negative impacts of introduction. The climate matching analysis for the contiguous United States indicates establishment concern for this species. Areas with the highest climate match are in the coastal Southeast, Southwest, and California. The Certainty of Assessment for this ERSS is classified as High due to the availability of abundant, clear, and convincing information about M. tuberculata’s distribution and negative impacts of introduction from peer-reviewed, scientific literature. The Overall Risk Assessment Category for M. tuberculata in the contiguous United States is High.