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Nahum,Laila Alves; Pereira,Sérgio Luiz; Campos Fernandes,Flora Maria de; Russo Matioli,Sergio; Wajntal,Anita. |
Partial cytochrome b and 12S rDNA mitochondrial DNA sequences of eight representatives of the Ramphastidae family were analyzed. We applied the linearized tree method to identify sequences evolving at similar rates and estimated the divergence times among some of the taxa analyzed. After excluding Ramphastos tucanus and Capito dayi from our data set, the remaining taxa presented a constant rate of DNA substitution, and branch lengths could be re-estimated with a clock constraint using the maximum likelihood method. Branch lengths were calibrated assuming that Galliformes and Piciformes split around 100 million years ago (mya). Our results indicate that Ramphastinae, and probably Capitoninae, diverged from other Piciformes in the Late Cretaceous (~82 mya),... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Divergence times; K/T; Mass extinction; Cytochrome b; 12S rDNA; Paleogeography; Phylogeny. |
Ano: 2003 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572003000400003 |
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Chen, J.; Callac, P.; Parra, L.A.; Karunarathna, S.C.; He, M.-Q.; Moinard, M.; De Kesel, A.; Raspé, O.; Wisitrassameewong, K.; Hyde, K.D.; Zhao, R.-L.. |
Within Agaricus subg. Minores, A. sect. Minores remains a little-studied section due generally to its delicate sporocarps often lacking taxonomically relevant morphological characters. To reconstruct the section, using the recent taxonomic system based on divergence times, and to evaluate the species diversity of A. sect. Minores in the Greater Mekong Subregion, 165 specimens were incorporated in phylogenetic analyses. A dated tree based on nuclear ITS, LSU and tef1-α sequence data allowed us to better circumscribe A. subg. Minores and to propose a new subgenus, A. subg. Minoriopsis, which is only known from tropical and subtropical regions of the Americas. A larger tree based on ITS sequences indicated that, with 81 phylogenetic species, the reconstructed... |
Tipo: Article / Letter to the editor |
Palavras-chave: Agaricaceae; Agaricus sect. Minores; Divergence times; Multi-gene phylogeny; Taxonomy. |
Ano: 2017 |
URL: http://www.repository.naturalis.nl/record/628990 |
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