Hybridization of Penaeus setiferus (Linnaeus, 1767) and Penaeus schmitti Burkenroad, 1936 (Decapoda)

Hybrid crosses of females of Penaeus setiferus × males of Penaeus schmitti were obtained through artificial insemination. Mature females of P. setiferus (mean weight, 53 g ± 8.2 SD), collected from a wild population in the northwestern Gulf of Mexico, were inseminated with sperm of males of P. schmitti (mean weight, 27 g ± 5.3 SD) obtained from the western Caribbean Sea. Nauplii resulted from 7 of 19 artificial inseminations and were cultured to the subadult stage. Fertilization in all inseminations was less than 1\% (4-4,300 nauplii per spawn), and subsequent survival of nauplii to postlarvae averaged 47\%. Hybridization was confirmed by isozyme comparisons of parents and offspring using starch gel electrophoresis. Hybrids also exhibited uropod coloration typical of P. schmitti, the paternal phenotype, when sampled as subadults. Diagnostic differences between the parent species were found only by using a soluble protein stain and were not found in 11 specific enzymes tested. Sperm and ova were observed in mature hybrid offspring. These results are indicative of the phylogenetic relatedness and genomic compatibility of these species.