An assemblage of large-sized insect traces in paleosols from the middle Miocene of northern Patagonia related to the climatic optimum

A new assemblage of large insect trace fossils is recognized in paleosols the middle Miocene pyroclastic deposits from extra-Andean north Patagonia. This includes Racemusichnus jacobacciensis igen. isp. nov., largest fossil attributed to solitary insects. R. represented by clusters two seven thickly walled cylinders horizontally orientated paleosol. The cluster arrangement, its orientation, size and wall suggest a dung beetle, probably representative Geotrupidae as possible maker. ichnoassemblage, also comprising large-sized specimens Coprinisphaera ispp., Teisseirei barattinia Feoichnus challa, belongs Rosellichnus assemblage-SAPIA Ichnofacies. Mollic along with fossils, mammal remains previous data for this unit an open grassy habitat compatible high productive grass savannas, under temperate-warm seasonal subhumid climate. highly ecosystems related rise temperature occurred during Middle Climatic Optimum.