INVESTIGADORES
ESCAPA Ignacio Hernan
congresos y reuniones científicas
Título:
Mesozoic and Cenozoic record of Araucaria from Patagonia: integrating morphological information into the genus phylogeny.
Autor/es:
ESCAPA, IGNACIO; CÚNEO, RUBÉN; WILF, PETER
Lugar:
Providence
Reunión:
Congreso; Botany 2010; 2010
Resumen:
The conifer family Araucariaceae is one of the most emblematic plant
groups of the Southern Hemisphere, where its extant distribution is
confined. The family originally included two genera, Agathis and Araucaria, and recently a third one was added: the monotypic Wollemia. Araucaria
shows an extended fossil record with species recognized since the early
Mesozoic in both hemispheres. The record of Araucaria in Patagonia can
be traced from the Early Jurassic through present. Fossil and living Araucaria species are generally divided into four sections: Bunya , Intermedia , Araucaria (= Columbea ) and Eutacta. Fossil species of Araucaria
, especially those preserving seed cones, were often assigned to a
particular section within the genus based on few characters. Previous
phylogenetic analysis of Araucaria have exclusively included
molecular characters and therefore fossils were not considered. We
discuss the high diversity of fossil Araucaria in Southern South
America, including several new findings from the Jurassic, Cretaceous
and Paleogene. This extensive fossil record is evaluated in a
morphological phylogenetic matrix that also includes all the living
species of Araucaria and selected other representatives of the family. In this context, the first record and diversification of the Araucaria
sections are discussed. Further investigations on this subject must
include revisions of extant and fossil species in order to determine new
morphological characters, the extension of the taxon sampling, and the
combination with molecular data. Additionally, considerations on the
biogeography of the family in the southern hemisphere are considered on
light of the new records.