-We report the record of two members of one of the most destructive insect pests of turfgrasses from the Late Pleistocene of the Pampean region. The presence of Cyclocephala signaticollis and Diloboderus abderus 12,000 years BP enables us to consider them as paleobio-indicators besides studying them as agricultural pests. This work constitutes the very first record of the genus and species, and the first Quaternary record of Dynastinae in South America. Moreover, this is one of the first paleoentomological studies that take in consideration beetles as bioproxies for the Quaternary of Argentina, and allows us to adjust the paleoclimatic inferences made for the region. This finding argues against the classic interpretations that indicate arid environmental conditions in the Pampean region during the first pulses of post-glacial climate recovery.

No abstract

Late Pleistocene outcrops exposed in Buenos Aires province, Argentina, represent one of the most informative sources for paleoecological studies on South American fauna and flora. Several proxies have been used for studying Pleistocene environmental conditions in the Pampas, but only a few were based on paleoentomological data. The aims of this study are to present the first record of three species of darkling beetles from the late Pleistocene of Buenos Aires province and to provide new paleoenvironmental information. The sediments containing fossil insects correspond to the Guerrero Member of the Luján Formation and were dated between 12,100 ± 100 14C BP and 13,400 ± 200 14C BP. Specimens of Nyctelia picipes (Billberg), Epipedonota cristallisata Waterhouse and Scotobius pilularius Germar were identified. To provide information about past climate, the particular climate requirements of these species were analyzed by using the Mutual Climatic Range method. This association could indicate the first pulse of post-glacial climate recovery and the replacement by the insect fauna currently inhabiting the area. This study is one of the first approaches to the Quaternary paleoentomology of Argentina, and highlights the potential of paleoentomological information, when evaluated in combination with previous knowledge on global climate conditions after the last glacial maximum.

No abstract

No abstract