| dc.description.abstract | The gulf killifish (Fundulus grandis) is a widely distributed cyprinodontiform of ecological importance in salt marshes of the Gulf of Mexico. Both the reproductive strategy and apparently limited dispersal capabilities should translate into strong phylogeographic association to natal sites. This study is the first to characterize the patterns of genetic differentiation among Texas populations using mitochondrial DNA sequence data. DNA was extracted from fin clips obtained from specimens sampled in two Texas locations, Galveston and Corpus Christi. Patterns of sequence variation and the phylogeographic association of haplotypes were characterized for 1,253 bp of sequence of the mitochondrial DNA genes ND2 and ND5, and for a segment of the D-loop region for 55 individuals. A strong phylogeographic signal was uncovered, with Galveston showing larger values of haplotypic and nucleotide diversities than Corpus Christi. AMOVA identified significant (P < 0.05) differentiation between Galveston and Corpus Christi samples using all loci, thus rejecting the null hypothesis of panmixia. The results of this study represent a valuable baseline for future assessments of Fundulus grandis variation along the Texas Gulf Coast, including a planned study of differences in genetic variation of colonizing fauna in natural and restored marshes. | en |
