title: An integrative approach to understanding the evolution and diversity of Copiapoa (Cactaceae), a threatened endemic Chilean genus from the Atacama Desert.
abstract: OBJECTIVE
  Species of the endemic Chilean cactus genus Copiapoa have cylindrical or (sub)globose stems that are solitary or form (large) clusters and typically yellow flowers. Many species are threatened with extinction. Despite being icons of the Atacama Desert and well loved by cactus enthusiasts, the evolution and diversity of Copiapoa has not yet been studied using a molecular approach.
  
  
  METHODS
  Sequence data of three plastid DNA markers (rpl32-trnL, trnH-psbA, ycf1) of 39 Copiapoa taxa were analyzed using maximum likelihood and Bayesian inference approaches. Species distributions were modeled based on geo-referenced localities and climatic data. Evolution of character states of four characters (root morphology, stem branching, stem shape, and stem diameter) as well as ancestral areas were reconstructed using a Bayesian and maximum likelihood framework, respectively.
  
  
  RESULTS
  Clades of species are revealed. Though 32 morphologically defined species can be recognized, genetic diversity between some species and infraspecific taxa is too low to delimit their boundaries using plastid DNA markers. Recovered relationships are often supported by morphological and biogeographical patterns. The origin of Copiapoa likely lies between southern Peru and the extreme north of Chile. The Copiapó Valley limited colonization between two biogeographical areas.
  
  
  CONCLUSIONS
  Copiapoa is here defined to include 32 species and five heterotypic subspecies. Thirty species are classified into four sections and two subsections, while two species remain unplaced. A better understanding of evolution and diversity of Copiapoa will allow allocating conservation resources to the most threatened lineages and focusing conservation action on real biodiversity.
authors.affiliation: Ghent University Research Group Spermatophytes & Botanical Garden, K.L. Ledeganckstraat 35, 9000 Gent, Belgium Royal Botanic Gardens, Kew, Richmond, Surrey TW9 3AB, UK isabel.larridon@ugent.be.
authors.forename: Isabel
authors.initials: I
authors.lastname: Larridon
authors.affiliation: The EXSIS Project: Cactaceae Ex-Situ & In-Situ Conservation, Casilla 175, Buin, Chile.
authors.forename: Helmut E
authors.initials: HE
authors.lastname: Walter
authors.affiliation: Departamento de Botánica, Facultad de Ciencias Naturales & Oceanográficas, Universidad de Concepción, Casilla 160C, Concepción, Chile Instituto de Ecología & Biodiversidad, Universidad de Chile, Casilla 653, Santiago, Chile.
authors.forename: Pablo C
authors.initials: PC
authors.lastname: Guerrero
authors.affiliation: Instituto de Ecología & Biodiversidad, Universidad de Chile, Casilla 653, Santiago, Chile Departamento de Ciencias Ecológicas, Universidad de Chile, Las Palmeras 3425, Chile.
authors.forename: Milén
authors.initials: M
authors.lastname: Duarte
authors.affiliation: Jardín Botánico Nacional, Camino El Olivar 305 El Salto, Viña del Mar, Chile Facultad de Ciencias Agronómicas y de Los Alimentos, Pontificia Universidad Católica de Valparaíso, Casilla 4-D, Quillota, Chile.
authors.forename: Mauricio A
authors.initials: MA
authors.lastname: Cisternas
authors.affiliation: Departamento de Botánica, Facultad de Ciencias Naturales & Oceanográficas, Universidad de Concepción, Casilla 160C, Concepción, Chile.
authors.forename: Carol Peña
authors.initials: CP
authors.lastname: Hernández
authors.affiliation: Ghent University Research Group Spermatophytes & Botanical Garden, K.L. Ledeganckstraat 35, 9000 Gent, Belgium.
authors.forename: Kenneth
authors.initials: K
authors.lastname: Bauters
authors.affiliation: Ghent University Research Group Spermatophytes & Botanical Garden, K.L. Ledeganckstraat 35, 9000 Gent, Belgium.
authors.forename: Pieter
authors.initials: P
authors.lastname: Asselman
authors.affiliation: Ghent University Research Group Spermatophytes & Botanical Garden, K.L. Ledeganckstraat 35, 9000 Gent, Belgium.
authors.forename: Paul
authors.initials: P
authors.lastname: Goetghebeur
authors.affiliation: Ghent University Research Group Spermatophytes & Botanical Garden, K.L. Ledeganckstraat 35, 9000 Gent, Belgium Instituto de Ecología, A.C., Centro Regional del Bajío, Avenida Lázaro Cárdenas 253 61600 Pátzcuaro, Michoacán, Mexico.
authors.forename: Marie-Stéphanie
authors.initials: MS
authors.lastname: Samain
mesh_terms: D005075:Biological Evolution; D029421:Cactaceae / Q000145:classification / Q000235:genetics / Q000502:physiology*; D002677:Chile; D018744:DNA, Plant / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D010802:Phylogeny; D063148:Plant Dispersal; D018087:Plastids / Q000235:genetics; D017422:Sequence Analysis, DNA
chemical_list: D018744:DNA, Plant
keywords: Cactaceae; Cactoideae; Copiapoa; ancestral state reconstruction; cpDNA; evolutionary biogeography; infrageneric classification; morphology; phylogeny; systematics