Data from: Cryptic genetic diversity in the mottled rabbitfish Siganus fuscescens with mitochondrial introgression at a contact zone in the South China Sea
Ravago-Gotanco, Rachel June
de la Cruz, Talna Lorena, University of the Philippines Diliman
Pante, Ma. Josefa, University of the Philippines Diliman
Borsa, Philippe, Udayana University
Ravago-Gotanco, Rachel, University of the Philippines Diliman
Published Feb 12, 2019 on Dryad.
Cite this dataset
Ravago-Gotanco, Rachel June et al. (2019). Data from: Cryptic genetic diversity in the mottled rabbitfish Siganus fuscescens with mitochondrial introgression at a contact zone in the South China Sea [Dataset]. Dryad. https://doi.org/10.5061/dryad.b8649
The taxonomy of the mottled rabbitfish Siganus fuscescens species complex has long been challenging. In this study, we analyzed microsatellite genotypes, mitochondrial lineages, and morphometric data from 373 S. fuscescens individuals sampled from the northern Philippines and Hong Kong (South China Sea, Philippine Sea and Sulu Sea basins), to examine putative species boundaries in samples comprising three co-occurring mitochondrial lineages previously reported to characterize S. fuscescens (Clade A and Clade B) or S. canaliculatus (Clade C). We report the existence of two cryptic species within S. fuscescens in the northeast region of the South China Sea and northern Philippine Sea, supported by genetic and morphological differences. Individual-based assignment methods recovered concordant groupings of individuals into two nuclear genotype clusters (Cluster 1, Cluster 2) with (1) limited gene flow, if any, between them (FST = 0.241; P < 0.001); (2) low frequency of later-generation hybrids; (3) significant association with mitochondrial Clade A and Clade B, respectively; and (4) subtle yet significant body shape differences as inferred from geometric morphometric analysis. The divergence between mitochondrial Clade C and the two other clades was not matched by genetic differences at microsatellite marker loci. The occurrence of discordant mitonuclear combinations (20.5% of the total number of individuals) is thought to result from mitochondrial introgression, consistent with a scenario of demographic, and presumably spatial, post-Pleistocene expansion of populations from northern regions into a secondary contact zone in the South China Sea. Mitonuclear discordance due to introgression obscures phylogenetic relationships for recently-diverged lineages, and cautions against the use of mitochondrial markers alone for species identification within the mottled rabbitfish species complex in the South China Sea region.
Siganus fuscescens_Microsat_Genotypes_RRGotanco et al 2017
Microsatellite genotype data in csv format. Data collected from 12 microsatellite loci for 343 individuals. File description in the first row. Locus names are in the second row. Individual names are in the first column, followed by alleles.Alleles are coded as fragment sizes, in separate columns. Missing data are indicated by ‘?.’