Genetic divergence of Chilean long-tailed snake (Philodryas chamissonis) across latitudes: conservation threats for different lineages

Abstract

Artículo de publicación ISIAim The Chilean long-tailed snake (Philodryas chamissonis) has a wide distribution across different latitudes and ecosystems in Chile ranging from the south of the Atacama Desert (26 S) to the extremely humid Valdivian temperate rain forest (40 S). Throughout this vast distribution, which is isolated by the Andes mountain range on the east and the Pacific Ocean on the west, there are biogeographical boundaries and large geographical barriers that must have played an important role in the distribution of genetic diversity within this species. This study aimed at elucidating the evolutionary history of P. chamissonis in Chile by analysis of mitochondrial DNA sequences. Location Chile (29 41¢–38 23¢ S). Methods We extracted DNA from 66 tissue samples collected across different latitudes and amplified and sequenced the mitochondrial DNA control region and the NADH dehydrogenase subunit 4 gene for phylogenetic and population analysis. Results Four distinct haplogroups were identified for P. chamissonis. These are highly consistent with a latitudinal geographic pattern, different ecosystems and the increase in topography towards central Chile. Three of the four haplogroups are concentrated in central Chile (33 S latitude) where the highest herpetofaunal diversity of the country is found. The Maipo River acts as historical geographical barrier for the species influenced by Pleistocene glaciation cycles, leading to a marked phylogeographical boundary. A strong population structure was found for the species (Ust = 0.78, P < 0.0001), with a high haplotype diversity (h = 0.97 ± 0.01) and nucleotide diversity (p = 0.0151 ± 0.0077). Main conclusions At least three evolutionarily significant units (ESUs) were designated for the species, and these should be taken into account for conservation plans. Three of the four haplogroups found within P. chamissonis are already threatened because their distribution along central Chile overlaps with most of the largest cities in the country

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

“…Cytogenetic and molecular studies of the lizard L. monticola also showed a high level of genetic variation in this watershed, where the Maipo River would have acted as a geographic barrier, producing divergence between populations located on opposite banks (Lamborot and Eaton 1997;Torres-Pérez et al 2007). This result also concurs with the results of Sallaberry-Pincheira et al (2011) in the Figure 3 Geneland analysis with posterior probability isoclines which indicate extensions of the genetic groups found (I, II, III; see Figure 2B). Black dots indicate locations of the 23 analyzed localities; thick black lines indicate the geographic border of Chile.…”

“…Those authors identified the topography of the central Chile and oceanic barriers as the most important factors which limited the connectivity of populations among river basins. Finally, in a genetic study of populations of the colubrid Philodryas chamissonis from 29°to 38°S, Sallaberry-Pincheira et al (2011) found a high level of phylogeographic structure, four latitudinally differentiated haplogroups, and high levels of intrapopulational genetic diversity in the Maipo River basin (33°S).…”

Geographical differentiation and cryptic diversity in the monocled cobra, Naja kaouthia (Elapidae), from Thailand

“…The differentiation between northern and southern populations has also been reported in the king cobra (O. hannah) using phylogenetic analyses of ND2 and CR (Suntrarachun, Chanhome, & Sumontha, 2014), and other amphibian and reptile species (Inger & Voris, 2001). Population phylogenetic studies of other snake species, such as D. acutus (Huang et al, 2007), A. laevis (Lukoschek et al, 2008), P. chamissonis (Sallaberry-Pincheira et al, 2011), Gloydius brevicaudus (Ding, Gan, He, & Zhao, 2011), Vipera latastei/monticola group (Velo-Antón et al, 2012) and N. atra (Lin et al, 2014(Lin et al, , 2012, showed similar results to those of this study in finding that, for example, geography, climate, and/or distance correlate with regional genetic variation.…”

Genetics as a Tool for Biodiversity Conservation: Examples from Central America

“…A study by Sallaberry-Pincheira et al (2011) provides an example of how phylogeography can aid in the delineation of ESUs. This study sought to determine whether geographic boundaries throughout the range of the Chilean long-tailed snake ( Philodryas chamissonis) have led to significant genetic divergence among isolated populations.…”