Extinct Neuropterida of Brazil (Insecta: Neuroptera, Megaloptera, Raphidioptera)

ABSTRACT The currently-known extinct Neuropterida fauna of Brazil comprises 18 families, 55 genera and 99 species (Neuroptera: 15 families, 49 genera, 89 species; Raphidioptera: 1 family, 2 genera, 5 species, + 1 genus incertae sedis with 2 species; Megaloptera: 1 family, 2 genera, 2 species; Order incertae sedis: 1 family, 1 genus, 1 species). All of these species have been described since 1980 and they collectively constitute the overwhelming majority of extinct Neuropterida presently known from South America. Other than one species of Permithonidae (Neuropterida incertae sedis) described from the Late Permian Irati Formation (Paraná Basin) of Rio Grande do Sul state, all extinct Brazilian Neuropterida taxa are known only from the Early Cretaceous Crato Formation (Araripe Basin) in Ceará and Pernambuco states. Of the 35 authors who have contributed to the descriptive literature of this fauna over the past 42 years, the work of Brazilian paleontologists Rafael Gioia Martins-Neto [1954-2010] and Maria Aparecida Vulcano-d'Andretta [1921-2018] - who together contributed to the description of 67 species - is especially notable. However, since their deaths, extinct Neuropterida have received little attention from Brazilian scientists and most later work on this fauna has been undertaken by workers outside Brazil. We provide this updated synthesis of the extinct Neuropterida of Brazil in order to centralize baseline knowledge for this fauna, to support efforts to document and conserve Brazilian fossil sites, and to encourage future work on the fauna, particularly by the next generation of Brazilian paleoentomologists.

New evidence of feathers in the Crato Formation supporting a reappraisal on the presence of Aves

The preservation of delicate structures such as feathers is very rare in the paleontological record, due to the fragility of their components. Fossil feathers have been reported from approximately 50 deposits around the world, from the Late Jurassic to the Pleistocene. In Brazil initial findings consisted of a primary feather of a large bird found in the Tremembé Formation. Other occurrences are preserved in the Crato Formation, where several symmetrical and one single asymmetrical feather was found. Based on three new specimens and reassessing further feather occurrences we cannot confirm the presence of volant Aves in this deposit. The presence of an asymmetrical feather without barbules and hooks hints at the previous existence of a flightless animal within this deposit, possibly a flightlessness bird or a non-avian theropod. Conversely, the presence of a feather from morphotype II present in Tyrannosauroidea, Compsognathidae, Therizinosauroidea and Dromeosauridae, points to a non-theropod origin. Since there are no confirmed records of birds and other feathered archosaurs in the region to date, more evidence is required to identify the animal from which these structures originated.

A fossilização de estruturas de revestimento delicadas como as penas constitui um processo extremamente raro, principalmente pela fragilidade de seus componentes. São conhecidos apenas cinquenta depósitos com esta natureza de registro (do Jurássico ao Terciário). No Brasil a primeira referência data de 1916, descrevendo uma pena de vôo com características plumáceas da Formação Tremembé (Bacia de Taubaté). Outras evidências, são provenientes dos calcários laminados da Formação Crato, apresentando registros de penas assimétricas e apenas uma simétrica. Com base em novos achados e reavaliando penas previamente descritas, verificou-se que não se pode afirmar a presença de Aves voadoras nestes depósitos. Isto se deve a ausência de estruturas exclusivas deste tipo de hábito, a exemplo de penas assimétricas com bárbulas e ganchos. Ao contrário disso, verificou-se que os registros apontam mais para a presença de animais emplumados não voadores, como terópodes não avianos ou Aves que tenham perdido secundariamente o voo. Reforçando esta ideia está a presença de uma pena pertencente ao morfótipo do estágio II encontrado até o momento em Tyrannosauroidea, Compsognathidae, Therizinosauroidea e Dromeosauridae. A ausência de registros confirmados de aves ou de outros arcossauros emplumados na região até o momento, geram expectativas sobre novos registros que apontem para os organismos detentores das penas encontradas neste depósito.