title: Population Genetic Structure and Species Status of Asiatic Toads (Bufo gargarizans) in Western China.
abstract: We investigated the population genetic structure of Asiatic toads (Bufo gargarizans) from the mountains of western China to determine their species status, using genotypic data of ten microsatellite DNA loci and DNA sequences from one mitochondrial gene. A total of 197 samples from eight sites were examined, which cover a large range of elevations (559-3457 m), as well as all three traditionally defined species (or subspecies). AMOVA did not reveal any particularly large among-groups structure, whether the sites were grouped by drainage, elevation, region, or species (subspecies). Individual assignment tests placed all samples into two genetic clusters, which largely corresponded to their geographic locations. An isolation-by-distance pattern was also detected when an outlier population (site 3) was excluded. Furthermore, a mitochondrial gene tree revealed deep divergence among haplotypes, sometimes within the same site. The clade patterns were partially associated with geographic distribution but had no resemblance to the traditional 2- or 3-species classification. Overall, these toad populations harbor a large amount of genetic diversity and have very high population differentiation, but taken together the evidence suggests that all populations belong to a single species. Our results are consistent with most previous molecular studies, and we recommend using Bufo gargarizans to represent all Asiatic toad populations from western China without subspecies division.
authors.affiliation: 1 Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, Sichuan 610041, China.
authors.forename: Guannan
authors.initials: G
authors.lastname: Wen
authors.affiliation: 1 Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, Sichuan 610041, China.
authors.forename: Weizhao
authors.initials: W
authors.lastname: Yang
authors.affiliation: 1 Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, Sichuan 610041, China.|2 Department of Integrative Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
authors.forename: Jinzhong
authors.initials: J
authors.lastname: Fu
mesh_terms: D063147:Animal Distribution; D000818:Animals; D002025:Bufonidae / Q000145:classification / Q000235:genetics*; D002681:China; D004247:DNA / Q000235:genetics; D049810:Genetic Speciation; D014644:Genetic Variation; D010802:Phylogeny; D013045:Species Specificity
chemical_list: D004247:DNA
keywords: Bufo gargarizans; genetic diversity; microsatellite loci; mtDNA sequences; population genetic structure; species status; western China