Artículo
A new calymmate mimosoid polyad from the Miocene of Argentina
Fecha de publicación:
05/2000
Editorial:
Elsevier Science
Revista:
Review of Palaeobotany and Palynology
ISSN:
0034-6667
Idioma:
Inglés
Tipo de recurso:
Artículo publicado
Clasificación temática:
Resumen
A palynomorph with an unequivocal relationship to the eight-grain polyads of the mimosoid genus Calliandra Benth., is described from the Miocene sediments of San Juan Province, Argentina. Comparison of the fossil palynomorph with polyads of the extant Calliandra species shows a resemblance to those which have one, highly specialized, appendiculate monad. The new palynomorph has a rudimentary appendix, apparently transitional in the path leading to the more highly developed appendiculate forms in the extant Calliandra group. This specialized polyad type is considered to be one of the most highly evolved forms in subfamily Mimosoideae. The closest affinity of the new fossil polyad is with the eight-grain calymmate polyads of Calliandra chilensis Benth., a species which has developed in the extra-tropical, xerophilous shrub, habitat of north-central Chile. The disappearance of Calliandra species in San Juan Province is thought to be related to the culmination of the Andean rising, and the consequent interruption to the Pacific Ocean climatic influence. This new discovery is the first fossil record of Calliandra for Argentina, as well as being the most southerly and the oldest. It reinforces the hypothesis of an early origin and diversification for the Leguminosae in Tropical America.
Palabras clave:
Appendiculate
,
Argentina
,
Calliandra
,
Calymmate
,
Eight-Grain Polyad
,
Miocene
Archivos asociados
Licencia
Identificadores
Colecciones
Articulos(MACNBR)
Articulos de MUSEO ARG.DE CS.NAT "BERNARDINO RIVADAVIA"
Articulos de MUSEO ARG.DE CS.NAT "BERNARDINO RIVADAVIA"
Articulos(SEDE CENTRAL)
Articulos de SEDE CENTRAL
Articulos de SEDE CENTRAL
Citación
Caccavari, Marta Alicia; Barreda, Viviana Dora; A new calymmate mimosoid polyad from the Miocene of Argentina; Elsevier Science; Review of Palaeobotany and Palynology; 109; 3-4; 5-2000; 197-203
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