Posted in Phylogenomics/Phylogeography on Dec 15, 2018
In a recent paper in Molecular Ecology on species delimitation, we invoke the age-old criterion of diagnosability to identify lineages that are candidates as name-bearing taxa. For SNP markers, fixed allelic differences between populations or metapopulations provide diagnosability. We apply these markers to a case study of a freshwater turtle, Emyduro macquorii, whose systematics has so far defied resolution, to bring to light a dynamic system of substantive allopatric lineages diverging on independent evolutionary trajectories, but held back in the process of speciation by low level and episodic exchange of alleles across drainage divides on various timescales.