Una nueva Podocarpácea fértil (Coniferal) del Cretácico inferior de Patagonia, Argentina

Abstract

The newgenus,Morenoa !milis from the earlycretaceousbeds of the Baqueró Formation (Santa Cruz Province,Argentina) is here described.'Ibis conifer is referred to the family Podocarpaceae on account of its vegetative a swell as reproductive male orpns that include bisaccate pollen grains.The ultrastructure of the leaf cuticle (of the Elatocladus type) and the pollen grains (of the Podocarpidites type) was studied with transmission electron microscopy.Comparisons with fossil and extant taJraof the family are also made, including the other three fossil genera known in fertile state from the same formation. The excellent preservation of the closed pollen sacs permitted the recognition of still inmature tetrads and a high inner content of Ubisch bodies. Epiphyllous fungí were also recognized on the leaf epidermis suggesting a mild'and humid c1imatic regime. Some degradation of the leaf cuticles was observed, possibly related in part to fungal activity.