Regional patterns of genetic structure among Australian populations of the mud crab, Scylla serrata (Crustacea : Decapoda): evidence from mitochondrial DNA

Abstract

The population genetic structure of the estuarine crab, Scylla serrata (Forskål, 1775), was examined among shelf-connected locations and across a historical bio-geographic barrier. Over 300 individuals were sampled from multiple locations within coastal regions (western, northern and eastern) of Australia and analysed for mutational differences at a mitochondrial coding gene (COI). Analysis of molecular variance indicated mitochondrial haplotypes to be structured regionally (P < 0.001), which contrasted with evidence of genetic panmixia within regions. Regional genetic structure broadly correlated with hydrological circulation, supporting the contention that release of propagules away from the estuary may allow genetic connectivity among widespread shelf-connected S. serrata populations. That similar patterns of maternal gene flow are absent among trans-oceanic populations may indicate that the spatial scale of effective dispersal for this species is generally limited to areas of coastal shelf. Two distinct clades of haplotypes were geographically separated either side of the Torres Strait, a narrow sea channel connecting the northern and eastern regions of coastal Australia. This pattern of historical genetic separation is concordant with a number of other marine species across northern Australia and may indicate a shared history of vicariance induced by eustasy. Alternatively, we suggest that sundering of S. serrata populations resulting in cladogenesis may have its origins outside of the northern Australian region.

Life-history, movement, and habitat use of Scylla serrata (Decapoda, Portunidae): current knowledge and future challenges

“…1). The Australian populations can be separated into two distinct clades (northern and eastern populations) divided by the Torres Strait (Gopurenko & Hughes, 2002). Local mud crab populations are not genetically distinct from each other, but can differ in phenotype (e.g., smaller sizes for southern distribution limit).…”

Morphological and genetic variability in Hippolyte obliquimanus Dana, 1852 (Decapoda, Caridea, Hippolytidae) from Brazil and the Caribbean Sea

“…Marine species with mobile phases in their life history are capable of a widespread dispersion and are, therefore, genetically homogeneous throughout their distribution (Gopurenko & Hughes, 2002); however, H. obliquimanus does not show such homogeneity. Possibly, the larvae of this species do not manage to cross the geographic barrier created by the Amazon River, or perhaps are restrained by other factors, such as the hydrodynamics of the marine currents, the dispersal limitation by larval behaviour, or the selection of local settlement (Broekaert, 2007).…”

Determination of Taxonomic Status and Phylogenetic Affinities of Common Edible Crab Species in Southern Coast of Sri Lanka Using DNA Barcoding Gene Region

“…Scylla serrate, commonly known as the giant mud crab, has been studied using DNA sequences by Fuseya and Watanabe [4]; Keenan et al [11] and Gopurenko and Hughes [6]. Costa et al [2] has highlighted the use of barcoding region of mitochondrial genome for the analysis of genetic data for crustaceans.…”