Biometric and allozymic characterization of three coastal and inland killifish populations (Pisces : Fundulidae) from the Peninsula of Baja California, Mexico

Type localities and/or central populations of coastal and inland killifishe s along the peninsula of Baja California were sampled to sun ey the biometr ic and allozymic relationships among them. The standard stepwise discrimina tory function analysis of biometric characters classified organisms into th ree well distinctive groups (p <0.001). The number of scales in the lateral series successfully split the species, while the caudal length/standard le ngth ratio did so between subspecies. Two diagnostic loci (PROT-2* and AAT- 2*) segregated private alleles in each taxon, Fundulus limra showed lower g enetic variability levels. than F. parvipinnis spp., in both polymorphism ( 18.8% in F. limit vs. 25.0% in F. parvipinnis spp.:) and expected heterozyg osity (0.060 in F lima vs 0.099 in F. p. hi brevis and 0.089 in F. parvipin nis). The reduced genetic variability in the threatened species F. lima may be related to its evolutionary history. Nei's genetic distance between F. lima and F p, parvipinnis was 0.247, while 0.075 between F. parvipinnis spp .