Resumen

PARDO-TRUJILLO, ANDRÉS  y  SANCHEZ, CARLOS A.. Cyclusphaera in the Cenozoic of Colombia and its supposed marine origin. Caldasia [online]. 2009, vol.31, n.1, pp.105-121. ISSN 0366-5232.

The occurrence of Cyclusphaera in Amagá (Cauca Valley) and La Paz (Middle Magdalena Valley basin) formations was studied. The genus Cyclusphaera has been incorrectly used as an indicator of marine conditions. Schuller & Doubinger (1970) did a mistake in the translation of Elsik (1966) about the association of this genus with marine palynomorphs. The data obtained in this study show that Cyclusphaera is often found in low percentages and associated with terrestrial organic matter and terrestrially-derived microfossils (e.g. pollen, spores and Pediastrum). Cyclusphaera equatorial diameter of the Amaga and La Paz formations is notably smaller than the species described in the Campanian of Peru and some early Cretaceous species from Argentina, where recently has been proved a relationship between Cyclusphaera and the conifers. A world distribution of Cyclusphaera from the early Cretaceous to Neogene is also presented.

Palabras clave : Cyclusphaera; Amagá; Middle Magdalena Valley; Tertiary; paleoenvironment.

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