MICROSATELLITE ANALYSIS OF POPULATION STRUCTURE IN THE SANTA ANA SPECKLED DACE (Rhinichthys osculus): CONSERVATION AND EVOLUTION

RM 215-218

Geographic isolation and habitat fragmentation can cause a population to undergo independent evolutionary trajectories. Stream dwelling vertebrates such as the minnows belonging to the Cyprinidae family, one of the most genetically variable and geographically distributed groups, are excellent models for examining the genetic effects of population isolation and substructure. Rhinichthys osculus, a freshwater minnow, is a local species of concern that inhabits the Santa Ana and San Gabriel watershed systems within the Southern California region. 23 polymorphic microsatellite loci were characterized and identified for Rhinichthys osculus in conjunction with the Savannah River Ecology Lab. Currently, approximately 150 samples of Rhinichthys osculus are being genotyped across 7 microsatellite loci to examine various population genetic parameters including population structure and the identification of unique alleles. Preliminary analysis has begun on two of the loci, Rhos 5 and Rhos 9, in which unique alleles, genetic diversity, and population structure have been examined. The completed data across the seven microsatellite loci will assist in potential conservation management strategies.