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Buyck B.,CNRS Systematics, Biodiversity and Evolution Institute | Kauff F.,University of Kaiserslautern | Eyssartier G.,boulevard Stalingrad | Couloux A.,Center National Of Sequencage | Hofstetter V.,Agroscope Changins Wadenswil Research Station ACW
Fungal Diversity | Year: 2014

After a short historical overview of past systematic studies on Cantharellus, discussing delimitation and species diversity of the genus as well as previous, morphology-based, infrageneric classifications, this paper presents the first molecularly-based infrageneric classification of this genus using a multigene phylogenetic approach (nucLSU, mitSSU, RPB2 and tef-1) on a dataset that covers approximately halve of the described chanterelles worldwide, including many type specimens. Six subgenera are recognized and the recognition of subgenus Afrocantharellus as a separate genus is not accepted. The taxonomic value of individual morphological features is discussed as challenged by this new multigene phylogeny which comprises five new sections, one new subgenus and many emendations for previously recognized infrageneric groups. The paper discusses the observed discrepancy in biodiversity of Cantharellus when comparing between studies that focus either on below- or above-ground presence. A preliminary biogeographic hypothesis suggests an 'out of Africa' Gondwanan origin as a result of vicariance and subsequent migrations. © 2013 Mushroom Research Foundation. Source

Hofstetter V.,Agroscope Changins Wadenswil ACW | Buyck B.,CNRS Systematics, Biodiversity and Evolution Institute | Croll D.,ETH Zurich | Viret O.,Agroscope Changins Wadenswil ACW | And 2 more authors.
Fungal Diversity | Year: 2012

Esca disease, which attacks the wood of grapevine, has become increasingly devastating during the past three decades and represents today a major concern in all wine-producing countries. This disease is attributed to a group of systematically diverse fungi that are considered to be latent pathogens, however, this has not been conclusively established. This study presents the first in-depth comparison between the mycota of healthy and diseased plants taken from the same vineyard to determine which fungi become invasive when foliar symptoms of esca appear. An unprecedented high fungal diversity, 158 species, is here reported exclusively from grapevine wood in a single Swiss vineyard plot. An identical mycota inhabits wood of healthy and diseased adult plants and presumed esca pathogens were widespread and occurred in similar frequencies in both plant types. Pioneer esca-associated fungi are not transmitted from adult to nursery plants through the grafting process. Consequently the presumed esca-associated fungal pathogens are most likely saprobes decaying already senescent or dead wood resulting from intensive pruning, frost or other mecanical injuries as grafting. The cause of esca disease therefore remains elusive and requires well executive scientific study. These results question the assumed pathogenicity of fungi in other diseases of plants or animals where identical mycota are retrieved from both diseased and healthy individuals. © 2012 The Author(s). Source

Nattier R.,CNRS Systematics, Biodiversity and Evolution Institute | Robillard T.,CNRS Systematics, Biodiversity and Evolution Institute | Desutter-Grandcolas L.,CNRS Systematics, Biodiversity and Evolution Institute | Couloux A.,Center National Of Sequencage | Grandcolas P.,CNRS Systematics, Biodiversity and Evolution Institute
Journal of Biogeography | Year: 2011

Aim A New Caledonian insect group was studied in a world-wide phylogenetic context to test: (1) whether local or regional island clades are older than 37Ma, the postulated re-emergence time of New Caledonia; (2) whether these clades show evidence for local radiations or multiple colonizations; and (3) whether there is evidence for relict taxa with long branches in phylogenetic trees that relate New Caledonian species to geographically distant taxa. Location New Caledonia, south-west Pacific. Methods We sampled 43 cricket species representing all tribes of the subfamily Eneopterinae and 15 of the 17 described genera, focusing on taxa distributed in the South Pacific and around New Caledonia. One nuclear and three mitochondrial genes were analysed using Bayesian and parsimony methods. Phylogenetic divergence times were estimated using a relaxed clock method and several calibration criteria. Results The analyses indicate that, under the most conservative dating scenario, New Caledonian eneopterines are 5-16 million years old. The largest group in the Pacific region dates to 18-29Ma. New Caledonia has been colonized in two phases: the first around 10.6Ma, with the subsequent diversification of the endemic genus Agnotecous, and the second with more recent events around 1-4Ma. The distribution of the sister group of Agnotecous and the lack of phylogenetic long branches in the genus refute an assumption of major extinction events in this clade and the hypothesis of local relicts. Main conclusions Our phylogenetic studies invalidate a simple scenario of local persistence of this group in New Caledonia since 80Ma, either by survival on the New Caledonian island since its rift from Australia, or, if one accepts the submergence of New Caledonia, by local island-hopping among other subaerial islands, now drowned, in the region during periods of New Caledonian submergence. © 2011 Blackwell Publishing Ltd. Source

Buyck B.,French Natural History Museum | Kauff F.,University of Kaiserslautern | Cruaud C.,Center National Of Sequencage | Hofstetter V.,Agroscope Changins Wadenswil Research Station ACW
Fungal Diversity | Year: 2013

The authors present a combined morphological and molecular approach of the genus Cantharellus in Africa. Morphological descriptions and detailed illustrations are provided for five new species from the Zambezian savannah woodlands in tropical Africa: C. afrocibarius, C. gracilis, C. humidicolus, C. miomboensis and C. tanzanicus. A maximum likelihood analysis of tef-1 sequences obtained for 83 collections of Cantharellus that are representative of all major groups in world wide Cantharellus, places a total of 13 African chanterelles, including the five newly described taxa. The recognition of a separate genus Afrocantharellus is rejected. An identification key based on the re-examination of all existing type material is provided for all presently known African Cantharellus. © 2012 Mushroom Research Foundation. Source

Hassanin A.,CNRS Systematics, Biodiversity and Evolution Institute | An J.,CNRS Systematics, Biodiversity and Evolution Institute | Ropiquet A.,Stellenbosch University | Nguyen T.T.,CNRS Systematics, Biodiversity and Evolution Institute | Couloux A.,Center National Of Sequencage
Molecular Phylogenetics and Evolution | Year: 2013

Mitochondrial sequences are widely used for species identification and for studying phylogenetic relationships among closely related species or populations of the same species. However, many studies of mammals have shown that the maternal history of the mitochondrial genome can be discordant with the true evolutionary history of the taxa. In such cases, the analyses of multiple nuclear genes can be more powerful for deciphering interspecific relationships. Here, we designed primers for amplifying 13 new exon-primed intron-crossing (EPIC) autosomal loci for studying shallow phylogeny and taxonomy of Laurasiatherian mammals. Three criteria were used for the selection of the markers: gene orthology, a PCR product length between 600 and 1200 nucleotides, and different chromosomal locations in the bovine genome. Positive PCRs were obtained from different species representing the orders Carnivora, Cetartiodactyla, Chiroptera, Perissodactyla and Pholidota. The newly developed markers were analyzed in a phylogenetic study of the tribe Bovini (the group containing domestic and wild cattle, bison, yak, African buffalo, Asian buffalo, and saola) based on 17 taxa and 18 nuclear genes, representing a total alignment of 13,095 nucleotides. The phylogenetic results were compared to those obtained from analyses of the complete mitochondrial genome and Y chromosomal genes. Our analyses support a basal divergence of the saola (Pseudoryx) and a sister-group relationship between yak and bison. These results contrast with recent molecular studies but are in better agreement with morphology. The comparison of pairwise nucleotide distances shows that our nuDNA dataset provides a good signal for identifying taxonomic levels, such as species, genera, subtribes, tribes and subfamilies, whereas the mtDNA genome fails because of mtDNA introgression and higher levels of homoplasy. Accordingly, we conclude that the genus Bison should be regarded as a synonym of Bos, with the European bison relegated to a subspecies rank within Bos bison. We compared our molecular dating estimates to the fossil record in order to propose a biogeographic scenario for the evolution of Bovini during the Neogene. © 2012 Elsevier Inc. Source

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