Widespread co-occurrence of divergent mitochondrial haplotype lineages in a Central American species of poison frog (Oophaga pumilio)

Abstract

Since the advent of phylogeography, amphibians have served as an exemplar group of organisms, showing strong geographical structuring of genealogical divergence (Avise, 2000). The diversity of phylogeographic patterns observed across organisms was categorized by Avise (2000), who combined the genetic distance between major lineages [deep (> 3% mitochondrial sequence divergence) versus shallow] and the geographic distribution (allopatric versus sympatric) of these lineages. Historical biogeographical factors as well as ecology and behaviour jointly affect population genetic patterns. ABSTRACTAim To analyse the phylogeographic structure of the strawberry poison frog, Oophaga pumilio (Dendrobatidae), across a large part of its range using a combination of mitochondrial and nuclear markers.Location Costa Rica and Panama.Methods Sequence analyses of a mitochondrial (cytochrome b) and a nuclear (RAG-1) gene fragment as well as analyses of seven microsatellite loci were carried out on 269 individuals of O. pumilio sampled from 24 localities and on two individuals of O. vicentei.Results Two main mitochondrial haplotype lineages, corresponding to a northern (north Costa Rica) and a southern (south Costa Rica and eastern Panama) lineage, were identified. They differed by up to 7% uncorrected distance. We observed co-occurrence of both lineages in seven populations in Costa Rica and Panama, indicating a pattern of extensive admixture. The two main mitochondrial lineages of O. pumilio roughly corresponded to a previously described phylogeographic pattern. Microsatellites indicate admixture spanning over a wide geographic area, but significant variation between the northern and southern groups was also found with microsatellite data. While microsatellite data reconstructed a separation south of an assumed Caribbean valley barrier, mitochondrial haplotypes of the 'southern lineage' shifted this barrier towards the north.Main conclusions Despite admixture, all three markers showed significant variation between the northern and southern groups. Phylogeographical breaks known from other anuran species in the study region could not be verified for O. pumilio. The unexpected clustering of the population from Escudo de Veraguas and the individuals of O. vincentei with the northern O. pumilio lineage indicates the need for a fundamental and careful taxonomic revision, including an interspecific phylogeography of the entire genus.

Hybridization of two ancient salamander lineages: molecular evidence for endemic spectacled salamanders on the Apennine peninsula

“…Whereas the primers for POMC were designed based on sequences obtained with POMC‐DRV‐F+R (Vieites, Min & Wake, 2007), primers for RAG‐1 were designed based on sequence information for Salamandrina obtained with other amphibian primers that are used in our laboratory. PCR amplifications were performed and amplicons cleaned and sequenced as described in Hauswaldt et al (2010). Annealing temperatures for amplifications of gene segments were 50.7 °C for the Cyt b gene, 57 °C for the POMC and 54 °C for the RAG‐1 gene.…”

Genetic divergence in tropical anurans: deeper phylogeographic structure in forest specialists and in topographically complex regions

“…Although most amphibians studied to date show such deep phylogeographic structure (Avise 2000(Avise , 2009Vences and Wake 2007;Wells 2007;Zeisset and Beebe 2008), numerous examples for amphibian species of shallow, unstructured phylogeography exist, often corresponding to temperate species characterized by fast postglacial range expansions (Babik et al 2004;Kuchta and Tan 2005;Crottini et al 2007;Vásquez et al 2013;Vences et al 2013) but also species for which such glacial influences are more difficult to invoke (Carnaval 2002;Burns et al 2007;Rabemananjara et al 2007;Makowsky et al 2009). Furthermore, examples of deep haplotype lineages that are poorly geographically structured and even occur in sympatry have been reported for some tropical species such as Agalychnis callidryas (Robertson et al 2009) and Oophaga pumilio (Hauswaldt et al 2011). Phylogeographically unstructured amphibian species are often generalists (Carnaval 2002), live in open habitats (e.g., Makowsky et al 2009), and reproduce in lentic water (summary in Vences and Wake 2007), but these presumed correlations still require proper testing.…”

Mitochondrial introgressive hybridization following a demographic expansion in the tomato frogs of Madagascar, genus Dyscophus

“…; Hauswaldt et al . ) and (iii) for species paraphyletic with respect to their mitochondrial genome, suggesting the occurrence of mitochondrial introgression (Babik et al . ; Shimada et al .…”