High allozyme variation and genetic similarity of two populations of commercial penaeids, Penaeus brevirostris (Kingsley) and P-vannamei (Boone), from the Gulf of California

Genetic resources assessment is considered as the starting point for popula tion management in both fisheries and aquaculture, In this study, we have o btained genetic variability measures of two commercial penaeid shrimp speci es, Penaeus brevirostris (Kingsley) and P. vannamei (Boone), from the Gulf of California by means of starch electrophoresis analysis of 16 enzymatic s ystems, plus total protein. Thirty-two loci were resolved, which revealed p olymorphism values (P-95) Of 15.63% in P. brevirostris and 25.00% in P. van namei. Unbiased expected heterozygosity (H-e) was 0.076 and 0.105 respectiv ely. These are high genetic variability figures, taking into account the pr eviously low genetic variability, assessed by means of allozyme variation, reported in several penaeid species around the world. Nei's genetic similar ity between the two species is 0.891.