Primeras evidencias de interacción insecto-planta en el Neógeno del noroeste de la Argentina

Abstract

This study provides the first evidence for plantinsect associations from fossil leaf impressions of the San José and Palo Pintado formations, dated as middle and upper Miocene age, from northwestern Argentina. The size, shape and arrangement of leaf damage on several plant hosts consists of various chew marks made by mandibulate insects occurring along the leaf blades of Malvaciphyllum quenquiadensis Anzo ́tegui and Cristalli (Malvaceae), hole feeding along the leaf edge of Nectandra saltensis Anzo ́tegui (Lauraceae), mines within the internal tissues of M. quenquiadensis, and oviposition scars in Cedrela sp. (Meliaceae). Based on specific, identifiable features of the plant damage, the likely producers responsible for this damage include external foliage feeders such as Orthoptera, Phasmoptera and Coleoptera; leaf miners from the Lepidoptera but possibly Hymenoptera and Diptera; and ovipositing insects representing the Odonata. Many of these insect groups were previously known from earlier Paleogene deposits of Argentina, and similar ovipositional damage has been documented from the early Eocene of Rio Negro and middle Eocene of Chubut in Patagonia, indicating geochronological continuity and occurrence in marsh and open woodland plant communities under warm and seasonal climatic conditions. © 2011 by the Sociedade Brasileira de Paleontologia.