FOSSIL SEEDS FROM THE LA CANTERA FORMATION, EARLY CRETACEOUS, SAN LUIS PROVINCE, ARGENTINA

GÓMEZ, MARÍA A.; GABRIELA GRISELDA PUEBLA; MERCEDES B. PRÁMPARO; ANDREA B. ARCUCCI

Acta Palaeobotanica

W. Szafer Institute of Botany, Polish Academy of Sciences, Kraków

Año: 2020 vol. 60 p. 181 - 198

2082-0259

Fossil seeds recovered from the La Cantera Formation, Lower Cretaceous, San Luis Basin, are the focus of the present contribution. We establish a new species, Carpolithus alatus and describe other specimens attributed to Carpolithus spp. and Ephedra canterata. The botanical affinity of winged seeds assigned to Carpolithus alatus is discussed in relation to the fossil flora recovered from this formation. Based on the abundance of Gnetales in the San Luis Basin (pollen grains, reproductive and vegetative structures assigned to Ephedra) we propose that Carpolithus alatus is affiliated with Gnetales (Weltwitschia). We suggest that Carpolithus spp. seeds might be angiospermous, because this group, represented by leaves and flowers, dominates the fossil macroflora of the La Cantera Formation. The micro- and macrofloral analysis of the La Cantera Formation and assessment of available dispersal vectors suggests that wind (anemochory) and water (hydrochory) may have been the most important dispersion strategies for these seeds. The abundance and small size of seeds recovered from the La Cantera Formation, together with their morphological characters, such as the presence of wings in Carpolithus alatus also favours abiotic mechanisms of dispersion such as anemochory or hydrochory