Because human actions alter the physical nature of aquatic ecosystems similarly worldwide, the extinction risk among many freshwater fishes that share particular life-history traits may also be similar. Determining whether taxonomic selectivity, the preferential loss (or persistence) of certain species groups, exists among the world's freshwater fish families is then a key step in predicting future species declines and triaging future conservation efforts. We use binomial statistics to look for taxonomic patterns among the world's freshwater fish families currently at risk of extinction. Families are identified as being at risk of extinction if at least one species within a given family is classified as either extinct or at risk of extinction by the International Union for the Conservation of Nature's Redlist of Threatened Animals [Groombridge, B., Baillie, J., 1997. 1996 IUCN Red list of Threatened Animals. IUCN Gland, Switzerland and …