title: Genetics, Morphology, Advertisement Calls, and Historical Records Distinguish Six New Polyploid Species of African Clawed Frog (Xenopus, Pipidae) from West and Central Africa.
abstract: African clawed frogs, genus Xenopus, are extraordinary among vertebrates in the diversity of their polyploid species and the high number of independent polyploidization events that occurred during their diversification. Here we update current understanding of the evolutionary history of this group and describe six new species from west and central sub-Saharan Africa, including four tetraploids and two dodecaploids. We provide information on molecular variation, morphology, karyotypes, vocalizations, and estimated geographic ranges, which support the distinctiveness of these new species. We resurrect Xenopus calcaratus from synonymy of Xenopus tropicalis and refer populations from Bioko Island and coastal Cameroon (near Mt. Cameroon) to this species. To facilitate comparisons to the new species, we also provide comments on the type specimens, morphology, and distributions of X. epitropicalis, X. tropicalis, and X. fraseri. This includes significantly restricted application of the names X. fraseri and X. epitropicalis, the first of which we argue is known definitively only from type specimens and possibly one other specimen. Inferring the evolutionary histories of these new species allows refinement of species groups within Xenopus and leads to our recognition of two subgenera (Xenopus and Silurana) and three species groups within the subgenus Xenopus (amieti, laevis, and muelleri species groups).
authors.affiliation: Department of Biology, Life Sciences Building Room 328 McMaster University, Hamilton, Ontario, Canada.
authors.forename: Ben J
authors.initials: BJ
authors.lastname: Evans
authors.affiliation: Biomedical Sciences, Ontario Veterinary College, University of Guelph, Guelph, Ontario, Canada.
authors.forename: Timothy F
authors.initials: TF
authors.lastname: Carter
authors.affiliation: Department of Biological Sciences, University of Texas at El Paso, El Paso, Texas, United States of America.
authors.forename: Eli
authors.initials: E
authors.lastname: Greenbaum
authors.affiliation: Institute of Vertebrate Biology, Czech Academy of Sciences, Kvetna 8, Brno, Czech Republic.|Department of Zoology, National Museum, Prague, Czech Republic.
authors.forename: Václav
authors.initials: V
authors.lastname: Gvoždík
authors.affiliation: Department of Biological Sciences, Columbia University, New York, New York, United States of America.
authors.forename: Darcy B
authors.initials: DB
authors.lastname: Kelley
authors.affiliation: Department of Biology, Papadakis Integrated Sciences Building, Drexel University, Philadelphia, Pennsylvania, United States of America.
authors.forename: Patrick J
authors.initials: PJ
authors.lastname: McLaughlin
authors.affiliation: Département des Vertébrés Récents, Instítut Royal des Sciences Naturelles de Belgique, Brussels, Belgium.
authors.forename: Olivier S G
authors.initials: OS
authors.lastname: Pauwels
authors.affiliation: Museum of Vertebrate Zoology, University of California, Berkeley, California, United States of America.
authors.forename: Daniel M
authors.initials: DM
authors.lastname: Portik
authors.affiliation: California Academy of Sciences, San Francisco, California, United States of America.
authors.forename: Edward L
authors.initials: EL
authors.lastname: Stanley
authors.affiliation: School of Biological Sciences, University of Bristol, Bristol, United Kingdom.
authors.forename: Richard C
authors.initials: RC
authors.lastname: Tinsley
authors.affiliation: Department of Zoology, National Museum, Prague, Czech Republic.
authors.forename: Martha L
authors.initials: ML
authors.lastname: Tobias
authors.affiliation: California Academy of Sciences, San Francisco, California, United States of America.
authors.forename: David C
authors.initials: DC
authors.lastname: Blackburn
mesh_terms: D000350:Africa, Central; D000354:Africa, Western; D000818:Animals; D005075:Biological Evolution; D058893:DNA Barcoding, Taxonomic; D004272:DNA, Mitochondrial; D006239:Haplotypes; D006824:Hybridization, Genetic; D059785:Karyotype; D010641:Phenotype; D010802:Phylogeny; D058974:Phylogeography; D011123:Polyploidy; D014981:Xenopus / Q000033:anatomy & histology* / Q000145:classification / Q000235:genetics*
chemical_list: D004272:DNA, Mitochondrial