%0 Journal Article
%T Mesozoic Coleopteran Faunas from Argentina: Geological Context, Diversity, Taphonomic Observations, and Comparison with Other Fossil Insect Records
%A Mar¨ªa Bel¨¦n Lara
%A Oscar Florencio Gallego
%A Lara Vaz Tassi
%J Psyche
%D 2012
%I Hindawi Publishing Corporation
%R 10.1155/2012/242563
%X The order Coleoptera is the most diversified group of the Class Insecta and is the largest group of the Animal Kingdom. This contribution reviews the Mesozoic insects and especially the coleopteran records from Argentina, based on bibliographical and unpublished materials (86 described species, 526 collected specimens). The material came from different geological units from the late Middle Triassic to the Late Triassic (Bermejo, Cuyo, and Malarg¨¹e basins) to the Middle-Late Jurassic and Early Cretaceous (Deseado Massif, Ca£¿ad¨®n Asfalto, and San Lu¨ªs Basin). The coleopteran record is composed of 29 described species with 262 collected specimens (isolated elytra) mainly represented by Triassic species and only four specimens recorded in Jurassic units, all of them currently unpublished. These fossil coleopterans provide fundamental information about the evolution of insects in the Southern Hemisphere and confirm the Triassic Argentinean insect deposits to be among the most important in the world. 1. Introduction Continental invertebrate communities from the Mesozoic Era are represented principally by two phyla: Arthropoda and Mollusca. Arthropods constitute the most abundant and diverse fossil record in lacustrine sequences of Argentina with ¡°conchostracans¡±, insects and ostracods as most representative groups. The mollusks, represented by bivalve and occasionally gastropods, have a low diversity and restricted distribution [1]. The recent insects constitute the richest class in terms of species diversity with estimates ranging from 3 to 50 million species [2¨C5]. There are 1275 families of known insects in the fossil record and 967 presently existing, of which 70% are also known as fossils [6, 7]. The data from insect families/genera indicate that the group¡¯s growth model follows an exponential curve of evolution, contrary to the occurrence of new orders, which declines [8, 9]. The Coleoptera represents the most diverse order within the Class Insecta, both taxonomically and ecologically. In addition, it is the most specious group in the Animal Kingdom with the number of described modern species exceeding 350,000, representing about 40% of the known insect fauna [10]. This diversity is probably related to certain features that allow adult living in restricted niches while retaining their ability to fly [10]. The systematics and phylogeny of fossil beetles is a very complex area, with old and new proposals and numerous publications which surprisingly still not clear this question. Most studies use different methodologies and are based mainly on adult
%U http://www.hindawi.com/journals/psyche/2012/242563/