title: Anonymous nuclear markers reveal taxonomic incongruence and long-term disjunction in a cactus species complex with continental-island distribution in South America.
abstract: The Pilosocereus aurisetus complex consists of eight cactus species with a fragmented distribution associated to xeric enclaves within the Cerrado biome in eastern South America. The phylogeny of these species is incompletely resolved, and this instability complicates evolutionary analyses. Previous analyses based on both plastid and microsatellite markers suggested that this complex contained species with inherent phylogeographic structure, which was attributed to recent diversification and recurring range shifts. However, limitations of the molecular markers used in these analyses prevented some questions from being properly addressed. In order to better understand the relationship among these species and make a preliminary assessment of the genetic structure within them, we developed anonymous nuclear loci from pyrosequencing data of 40 individuals from four species in the P. aurisetus complex. The data obtained from these loci were used to identify genetic clusters within species, and to investigate the phylogenetic relationship among these inferred clusters using a species tree methodology. Coupled with a palaeodistributional modelling, our results reveal a deep phylogenetic and climatic disjunction between two geographic lineages. Our results highlight the importance of sampling more regions from the genome to gain better insights on the evolution of species with an intricate evolutionary history. The methodology used here provides a feasible approach to develop numerous genealogical molecular markers throughout the genome for non-model species. These data provide a more robust hypothesis for the relationship among the lineages of the P. aurisetus complex.
authors.affiliation: Departamento de Biologia, Universidade Federal de São Carlos, Rodovia João Leme dos Santos km 110, Sorocaba, São Paulo 18052780, Brazil.
authors.forename: Manolo F
authors.initials: MF
authors.lastname: Perez
authors.affiliation: Department of Evolution, Ecology, and Organismal Biology, The Ohio State University, Columbus, OH, USA.
authors.forename: Bryan C
authors.initials: BC
authors.lastname: Carstens
authors.affiliation: Departamento de Biologia, Universidade Federal de São Carlos, Rodovia João Leme dos Santos km 110, Sorocaba, São Paulo 18052780, Brazil.
authors.forename: Gustavo L
authors.initials: GL
authors.lastname: Rodrigues
authors.affiliation: Departamento de Biologia, Universidade Federal de São Carlos, Rodovia João Leme dos Santos km 110, Sorocaba, São Paulo 18052780, Brazil. Electronic address: emarsola@ufscar.br.
authors.forename: Evandro M
authors.initials: EM
authors.lastname: Moraes
mesh_terms: D029421:Cactaceae / Q000145:classification* / Q000235:genetics*; D002467:Cell Nucleus / Q000235:genetics*; D002980:Climate; D005819:Genetic Markers; D062312:Islands; D018895:Microsatellite Repeats; D010802:Phylogeny; D058974:Phylogeography; D063148:Plant Dispersal; D018087:Plastids / Q000235:genetics; D017422:Sequence Analysis, DNA; D013020:South America
chemical_list: D005819:Genetic Markers
keywords: Climatic Niche Modelling; Molecular markers; Next generation sequencing; Non-model species; Phylogeography; Species tree