Fossil Coleoptera from the Pilauco Site: An Approach to Late Pleistocene Microenvironments

Abstract

Quaternary fossil beetles have been widely used as environmental indicators and reconstructions of past climate. In Chile, records of fossil Coleoptera range from ~28,000 to 5200 cal yr BP with the higher concentration of fossil sites in Patagonia. This chapter presents an overview of the aforementioned studies, with an emphasis on the taxonomic beetle composition and some environmental inferences of the Pilauco site. In Pilauco, 13 families and 21 species of fossil beetles have been described with age constraints ranging between 15,750 and 14,700 cal yr BP. Enochrus vicinus and Germainiellus dentipennis are the most abundant species at Pilauco. Based on the record of Coleoptera, was possible infer that the surrounding vegetation around Pilauco was dominated by forest of Nothofagus sp., grasslands and wetlands. Beetle assemblages also provide information regarding the relationship between megafauna and coleopterans. This is mainly because; large herbivorous mammals may have provided substrates for the subsistence of dung beetles and scavengers, acting at the same time as modifiers of the site conditions and promoting greater environmental heterogeneity. These results highlight the need to incorporate modern information of intraspecific species dynamics and disturbances to studies of environmental and climatic paleo reconstructions based on fossil beetles.