Calvillo-Canadell, Laura , Cevallos-Ferriz, Sergio .
New Oligocene fossil legumes from Los Ahuehuetes locality, Tepexi de Rodriguez, Puebla, Mexico.
In the last years diverse fossil legumes have been reported and identified from different localities in Mexico, these new materials contributed to understand diversity of Leguminosae in low latitude North America and allowed hypothesis to explain how the Oligocene paleoflora in the area was integrated. Using foliar architecture characters we described and identified two isolated leaflets similar to those of extant Havardia playloba (Mimosoideae) and Erythrina sp. (Papilionoideae); both are unilobed, elliptic and peciolulated leaflets with entire margin, and rounded apex, pinnate primary venation, brochidodromous secondary venation and reticulate-percurrent tertiary venation. They differ in the symmetry of the blade. The fossil similar to Havardia has asymmetric base and decurrent-convex shape, while the Erythrina-like fossil has asymmetric blade and truncated base. The third fossil represents a symmetric, sessile and rounded stipule with actinodromus primary venation, festooned brochidodromous secondary venation and erosed margin that compares closely with Senna latifolia (Caesalpinioideae). These new materials include members of the three Leguminosae subfamilies further suggesting an important Paleogene diversification process in the area. The presence of Havardia and Erythrina is consistent with the concept of the boreotropical flora extending to low latitude North America.
Log in to add this item to your schedule
1 - Instituto de Geologia, UNAM, Departamento de Paleontologia, Ciudad Universitaria, Delegacion Coyoacan,, Mexico, Distrito Federal, 04510, Mexico
2 - Department of Palentology, Instituto De Geología, Mexico, 01900, Mexico
Presentation Type: Oral Paper:Papers for Sections
Location: Williford A/Hilton
Date: Wednesday, July 11th, 2007
Time: 10:15 AM