Comparative phylogeography of codistributed species of ChileanLiolaemus(Squamata: Tropiduridae) from the central‐southern Andean range

Abstract

In this study, we used a recently developed supertrees method to test for shared phylogeographical signal in partially overlapping geographical ranges of lizards of the genus Liolaemus from the Andean Range in south-central Chile. We reconstruct mtDNA gene trees for three partially codistributed species (Liolaemus tenuis, L. lemniscatus and L. pictus), and our sampling effort is sufficient to allow statistical tests of shared signal between the combinations L. tenuis-L. pictus, and L. tenuis-L. lemniscatus. For both combinations, standardized maximum agreement subtrees scores showed statistically significant signal for shared pattern in regions of overlap, as evaluated by randomization tests (P < 0.001 and < 0.05, respectively). The matrix representation with parsimony tree obtained from the combination of the three different gene trees revealed concordant phylogeographical associations of all species, and was consistent with the geographical association of intraspecific haploclades with three Chilean bioclimatic zones. A multidimensional scaling analysis of several climate variables showed highly significant differences among these zones, which further suggests that they may have contributed to similar patterns of intraspecific divergence across all three species. In the mesomorphic zone in Central Chile, the species L. tenuis and L. lemniscatus may have codiverged in response to shared orogenic vicariant events, which likely predominated over climatic events associated with cycles of glacial advance and retreat. In the hygromorphic zone in southern Chile, however, glacial cycles likely predominated in structuring the phylogeographical histories of L. tenuis and L. pictus, although important ecological differences between these two caution against broad generalizations at this point.

Low phylogeographic structure of Rhinella arunco (Anura: Bufonidae), an endemic amphibian from the Chilean Mediterranean hotspot

“…The lowest values of haplotype diversity in R. arunco were found in localities in the extreme south of its range (haplotype D), which suggests an effect of glaciations on the genetic diversity of those populations, as postulated by Victoriano et al (2008) for L. lemniscatus, whose distribution is also limited to the Mediterranean zone, but is wider than that of R. arunco. Also, the value of Fu's Fs indicated signs of demographic expansion for haplogroup D, which had the lowest values of haplotype diversity.…”

“…Victoriano et al (2008) compared patterns of genetic variation of three lizard species of the genus Liolaemus sampled in different latitudinal ranges (Liolaemus tenuis, 31°t o 40°S; Liolaemus lemniscatus, 32°to 37°S; and Liolaemus pictus, 37°to 42°S). In L. lemniscatus, which mainly inhabits the Mediterranean zone, they found more genetic variation in populations of the extreme north compared to those of the south of its range.…”

Molecular phylogenetic analyses reveal the importance of taxon sampling in cryptic diversity: Liolaemus nigroviridis and L. monticola (Liolaeminae) as focal species

“…Despite our sampling bias, the high molecular divergence in L. nitidus may indicate a substantial history of genetic isolation among populations [68]. Quaternary fluctuations may have played a major role in the current population structure of lizards in Chile [6,38,79], connecting populations that may have been allopatric in the past [80].…”

“…Cytochrome b and cytochrome oxidase I are among the most common markers; they are particularly useful in phylogeography and species delineation studies [3][4][5][6][7][8].…”

Genetic structure of the giant kelp Macrocystis pyrifera along the southeastern Pacific

“…2). The impact of glaciations on the distribution and genetic variation of species in southern Chile has been documented, but mostly for terrestrial (Muellner et al 2004, Marchelli & Gallo 2006, Himes et al 2008, Rodriguez-Serrano et al 2008, Victoriano et al 2008 or freshwater biota , Xu et al 2009). A recent colonization, after the LGM and the retreat of sea ice, of Durvillaea antarctica in the subantarctic region by a series of long-distance rafting events has been suggested (Fraser et al 2009).…”