Cross-species testing and utility of microsatellite loci in Indirana frogs

The cross-species amplification success rate varied from 11.3？% to 29.0？% depending on the species, with 29 - 80？% of the amplifying loci being polymorphic. A strong negative correlation between cross-species amplification success (and polymorphism) and genetic distance separating target from source species was observed.Our results provide additional genetic support for the existence of genetically divergent cryptic species within the genus Indirana. The tested markers should be useful for population and conservation genetic studies in this genus, and in particular, for species closely related to the source species, I. beddomii.The fauna of the Indian Western Ghats biodiversity hotspot is well known for its diversity and high level of endemism [1]. In particular, there are many families and genera of amphibians that are unique to the region [2,3], with roughly 132 endemic species [4]. However, the amphibian diversity in this region remains inadequately characterized [5]. This is reflected by numerous taxonomic uncertainties and ambiguities [6], and in the fact that many species still await proper taxonomic description [7]. Frogs belonging to the endemic genus Indirana (Ranixalidae; [8]) are among the poorly studied amphibian genera from the Western Ghats [9]. At present, information regarding their interspecific and intraspecific differentiation and variability across the diverse and fragmented habitats of Western Ghats is very limited [10].An earlier study based on the examination of interspecific mitochondrial and nuclear sequence variability revealed a great deal of cryptic diversity within the Indirana genus; morphologically similar species displayed a high degree (4.2–17.1？%) of genetic divergence [10]. In order to further explore this differentiation, we have recently developed 62 polymorphic microsatellite loci for one of the Indirana species (I. beddomii; [11]). Here we report the results of cross-species amplification tests for these microsatellite loci in