Sporomorphs richness, extinction and origination during the Late Paleozoic of Argentina, Brazil, Bolivia and Uruguay

ALVES DE SOUZA, P; MARTÍNEZ-BLANCO, X.; VARELA, L., ; DI PASQUO, M.; BERI, Á,

Paraná

Simposio; XVII Simposio Argentino de Paleobotánica y Palinología,; 2018

ALPP y UADER

Diversity pa)erns of Pennsylvanian-Lopingian sporomorph genera of the Paraná (Brazil and Uruguay),Parnaíba and Amazonas (Brazil), Tarija and Paganzo (ArgenVna) and Madre de Dios (Bolivia) basinswere analyzed. The main aim of the present contribuVon was to address the effect of possiblesampling biases over diversity esVmaVons. We esVmated sporomorphs richness and sampling usingthe recently developed TRiPS method and modeled originaVon, exVncVon and sampling rates withthe implementaVon of Inverse Survivorship Models. Furthermore, we tested whether modelingdifferent sampling rates across Vme and independent parameters for spores and pollen grainssignificantly improved model fit. Results showed highest richness during the Cisuralian, withoriginaVon peaking at the Asselian and exVncVon being highest during the Kungurian. EsVmates ofsampling rate were high for most Vme intervals and results showed that modelling different samplingrates across Vme did not improve model fit. On the other hand, modelling originaVon and exVncVonrates independently for spores and pollen grains significantly improved model fit, indicaVng differentpa)erns of originaVon and exVncVon for spores and pollen grains. Overall, pollen grains showedhigher originaVon rates than spores except during the Kasimovian, while spores exhibited higherexVncVon rates than pollen grains except during the Guadalupian. Changes in total sporomorphsdiversity, as well as differences between spores and pollen grains, may be related to changing climaVccondiVons in Western Gondwana during the Late Paleozoic that could impact differently over plantcommuniVes.*Funding PIP CONICET 0812.