Extensive intraspecific genetic diversity of a freshwater crayfish in a biodiversity hotspot

Abstract

1. The freshwater crayfish Cherax dispar (Decapoda: Parastacidae) inhabits coastal regions and islands of South East Queensland, Australia. We hypothesised that populations of C. dispar on different islands would be more genetically divergent from each other than populations from different drainages within the same island or on the mainland. 2. Phylogenetic and phylogeographic analyses were conducted on two mitochondrial genes (cytochrome oxidase subunit I & 16S ribosomal DNA) and one nuclear gene (Internal Transcribed Spacer region 2). Phylogeographic patterns were compared with those for other freshwater organisms in the area. 3. Deep genetic divergences were found within C. dispar, including four highly divergent (up to 20%) clades. The geographic distribution of each of the clades revealed strong latitudinal structuring along the coast rather than structuring among the islands. The high genetic divergence observed among the C. dispar clades was estimated to have pre-dated island formation and may represent ancient river drainage patterns. 4. A restricted distribution was observed for the most divergent clade, which was discovered only on two of the sand islands (North Stradbroke Island and Moreton Island). Furthermore, strong phylogeographic structuring was observed within this clade on North Stradbroke Island, where no haplotypes were shared between samples from opposite sides of the island. This low connectivity within the island supports the idea that C. dispar rarely disperse terrestrially (i.e. across watersheds).

Contemporary genetic structure reflects historical drainage isolation in an Australian snapping turtle,Elseya albagula

“…An even stronger pattern of lineage disjunction occurs between the Fitzroy and the almost equally extensive Burdekin Catchment directly to its north (Unmack, ). Another inferred barrier occurs south of the Mary River, based on genetic data from various species including several fish (Hughes et al ., ; Wong, Keogh & McGlashan, ; Thacker et al ., ) and macroinvertebrates (Murphy & Austin, ; Sharma & Hughes, ; Bentley, Schmidt & Hughes, ). These barriers appear to define the natural distributional limits of Els.…”

The world in a grain of sand: evolutionarily relevant, small‐scale freshwater bioregions on subtropical dune islands

“…Dark areas are creeks, lakes or swamps. Dotted lines represent a priori island ‘sides’ (Page & Hughes, 2007a; Bentley et al. , 2010).…”

“…The present study grew out of a multi‐stranded risk analysis undertaken by the Queensland State government to document the ecological assets of NSI that depend on ground water (see Marshall, McGregor & Negus, 2006b). Existing data from two freshwater crustaceans on the island (Page & Hughes, 2007a; Bentley, Schmidt & Hughes, 2010) has suggested that there could be different communities on the eastern and western sides, meaning they could be complements and thus with potentially important implications for risk assessments and conservation plans. Data from the same two species (and studies) also implied that Fraser Island may also be bisected by a currently unappreciated border between freshwater communities, but this one between north and south.…”

Complexity of biogeographic pattern in the endangered crayfish Austropotamobius italicus in northern Italy: molecular insights of conservation concern

“…In freshwater crustaceans, cryptic variation has been repeatedly pointed out by the analysis of molecular polymorphisms at the mitochondrial gene encoding for the cytochrome c oxidase subunit I (COI) Witt et al 2006;Apte et al 2007;Bentley et al 2010;Dawkins et al 2010;Filipová et al 2010;Chiesa et al 2011;Klobučar et al 2013). Since genetic variability plays a crucial role in shaping the evolutionary paths for populations and species (e.g.…”