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Pollen, ostracods, diatoms and insects such as beetles and chironomids are the biological indicators from lake sediments more useful in environmental reconstructions. Chironomids have recently acquired great importance due to the promising results obtained regarding climatic reconstructions mainly in Europe and North America. In South America, the use of fossil chironomids in Quaternary studies is still limited and the reason for that is the little regional taxonomic knowledge. Most of these studies were developed in glacial lakes in Patagonia both in Argentina and Chile. The larvae of chironomids are an invaluable paleolimnological tool due to the sensitiveness of these insects to natural and non-natural environmental changes. In addition to that, this group of insects is widely distributed with a high abundance and diversity. Their head capsules can preserve in sediments holding characters which allow their generic and sometimes specific identification. The study of chironomid assemblages can be used with different goals, for instance, to study eutrofication due to their quick response to changes in organic matter, nutrients and heavy metals. However, one of the most significant potentials of this group is its sensitivity to temperature variations, which is why the most important implementation of their study in sediments is centered in climatic reconstructions. This article is a review of the studies developed in Argentinean and Chilean Patagonia, using fossil chironomids for paleoenvironmental reconstructions. [ABSTRACT FROM AUTHOR]

The Chironomidae (Diptera: Nematocera) family is one of the most widely distributed group of insects and often the most abundant in freshwater environments. Representatives of this family can exploit a wide range of environmental gradients. The information here presented is based on the compilation of distributional data obtained from bibliography, the study of the type material deposited in the Natural History Museum (UK) and the collection material from Museo de La Plata (Argentina). Nine subfamilies are recorded from Patagonia, being the monotypic subfamily Chilenomyiinae endemic for the area. From the 111 known genera from South America, 53 are present in the studied area. Approximately 20 % of the genera recorded from Patagonia are endemic and 7 of them have transantarctic relationships. In Patagonia there are 177 species of Chironomidae, out of which 98% are endemic, 3 % are considered nomina dubia and ca. 1 7 % requires revision since their systematic position is doubtful. The original descriptions of the chironomid species from Patagonia are based mainly on males (n=58) and males and females (n=43) both amounting to 57 % of the total, the rest of the species have been described using different combinations of stages from their life cycle. [ABSTRACT FROM AUTHOR]

El artículo discurre sobre el VII Congreso Argentino de Entomología en Córdoba, Argentina durante el mes de octubre de 2008. Los autores describen los temas principales del congreso, el cual fue dedicado al entomólogo argentino Mario Gentili, incluyendo presentaciones sobre la biodiversidad de insectos en la región de Patagonia.