Biodiversity and evolution of trout species in Mexico (Salmonidae: Onchorhynchus)

Authors: Richard L. Mayden, Casey B. Dillman, Anna Belia Santo Camarillo, Héctor Espinosa-Pérez, Francisco J. García de León, Bernard Kuhajda, Joseph Tomelleri, David L. Propst

Year: 2009 (xli)

Abstract

Resident freshwater trout of genus Oncorhynchus (Protacanthopterygii: Salmonidae) form a significant component of biodiversity in streams, rivers and lakes of western North America. While trout from the western United States and Canada have received extensive systematic and population genetic investigation, the full range of diversity from native trout endemic to the Sierra Madre Occidental (SMO) of northern Mexico has arguably received less study. Only recently has this native diversity receiving in depth investigation from the binational group Truchas Mexicanas for proposing systematic relationships and understanding population history. In this study we present the first phylogenetic hypothesis for this native fauna based on mtDNA sequence data from two loci. We place the recovered lineages in a geographic context and use these hypotheses for understanding the native diversity. Stocking of non-native Oncorhynchus threatens the native fauna through hybridization in some regions. A consortium of biologists from Mexico and the USA are diligently working to advise governmental agencies to enable information-based management of the native trout.