A New Trout from Central Mexico: Salmo chrysogaster, the Mexican Golden Trout

In August 1952, a beautiful, golden-coloredtrout was collected in the Rio Verde near Guadalupe y Calvo in southwestern Chihuahua. This trout was described, but not named, by Needham and Gard (1959). We did not name it at that time because we had little information concerning the amount of variability found in western North American members of the genus Salmo throughout its entire range. Before this trout was named we wanted to be confident that its distinctive characters had a genetic basis and were not mainly phenotypic expressions of local environmental phenomena. The compilation of data by Needham and Behnke (unpublished) on more than 2,000 specimens of the genus Salmo from western North America, collected from virtually their entire native range, has demonstrated that, indeed, the Mexican golden trout is a distinct group and worthy of taxonomic recognition. Taxonomic methods used are essentially those listed in Hubbs and Lagler (1949) with the modifications noted in Needham and Gard (1959).