Two late Pleistocene members of the white-grub complex, one of the most destructive insect pests of turfgrasses

Abstract

-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.

Synopsis of the cyclocephaline scarab beetles (Coleoptera, Scarabaeidae, Dynastinae)

“…A fossilized elytron and pronotum of an unsexed C. signaticollis individual were discovered in Buenos Aires Province, Argentina (Ramírez and Alonso 2016). The fossil is from the Late Pleistocene (Tarantian Stage) and the sediments containing the fossil dated between 12,100 ± 100 BP and 13,400 ± 200 BP (Ramírez and Alonso 2016).…”

“…A fossilized elytron and pronotum of an unsexed C. signaticollis individual were discovered in Buenos Aires Province, Argentina (Ramírez and Alonso 2016). The fossil is from the Late Pleistocene (Tarantian Stage) and the sediments containing the fossil dated between 12,100 ± 100 BP and 13,400 ± 200 BP (Ramírez and Alonso 2016). Neoichnological experiments demonstrated that C. borealis and C. lurida lurida larvae create diagnostic backfilled meniscate burrows and ellipsoidal chambers as they burrow through soil, while adults create poorly organized backfilled burrows (Counts and Hasiotis 2009).…”

First Record of Fossil Insects from the Middle Holocene of Tierra Del Fuego, Argentina

“…Studies from the Argentinean Pata-gonia (e.g., Ariztegui et al, 1997;Massaferro and Corley, 1998;Bianchi et al, 1999;Massaferro et al, 2004) are mainly focused on the paleolimnological implications of entomological studies and based on Chironomidae (Diptera). Quaternary fossil insects have been mentioned in some studies (e.g., Pardiñas et al, 1998;Petrulevičius, 1999;Voglino and Pardiñas, 2005), but only recent works have focused on them (e.g., Ramírez and Alonso, 2014;Ramírez and Alonso, 2016;Ramírez and Michat, 2016;.…”