High unexpected genetic diversity of a narrow endemic terrestrial mollusc
- Published
- Accepted
- Subject Areas
- Conservation Biology, Evolutionary Studies
- Keywords
- endemic species, terrestrial gastropods
- Copyright
- © 2016 Madeira et al.
- Licence
- This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ Preprints) and either DOI or URL of the article must be cited.
- Cite this article
- 2016. High unexpected genetic diversity of a narrow endemic terrestrial mollusc. PeerJ Preprints 4:e2405v1 https://doi.org/10.7287/peerj.preprints.2405v1
Abstract
A large array of species and species complexes from the Iberian Peninsula display strong genetic subdivisions indicative of past population isolation in separate glacial refugia as a result of survival throughout the Pleistocene ice ages. We used mitochondrial and nuclear sequence data to analyse phylogeographic patterns in a group of endemic land snails of the genus Candidula from a valley of central Portugal (Vale da Couda) showing an exceptionally narrow distributional range. Phylogenetic analyses recovered Vale da Couda specimens in two main clades that do not share a common ancestry. Considering the restricted geographic distribution, an unusual high number of haplotypes was found. These haplotypes were unevenly distributed among the sampling sites. Our results show a departure from the expectation that species with restricted distributions have low genetic variability. The putative past and contemporary models of geographic distribution of Vale da Couda lineages are compatible with a scenario of species co-existence in more southern locations during the last glacial maximum (LGM) followed by a post-LGM northern dispersal tracking the species optimal thermal, humidity and soil physical conditions. Mismatch analysis indicated a population expansion during the LGM, which corroborates our biogeographic scenario.
Author Comment
This is a submission to PeerJ for review.
Supplemental Information
Bioclimatic variables
Bioclimatic variables for current conditions retrieved from WorldClim dataset (Hijmans et al 2005).
Evolutionary divergence between haplogroups
Estimates of net evolutionary divergence between haplogroups (axis on the left, dark grey bars ± standard deviation) and within lineages (axis on the right, light grey bars ± standard deviation), based on Tamura-Nei distances.