Novos morfogêneros de lenhos fósseis gimnospérmicos provenientes do monumento natural das árvores fossilizadas do estado do Tocantins (Monaf), permiano, Brasil

Abstract

The Petrified Forest of Northern Tocantins (FPTS) is located in the southwest region of the Parnaíba Sedimentary Basin, and its most significant fragment gave rise to the Conservation Unit (UC) of Integral Protection Natural Monument of Fossilized Trees of the State of Tocantins (Monaf) . Fossils of tree ferns, sphenophytes and gymnosperms, among other groups, have been identified in the outcrops of Monaf and its surroundings. The various fossil plants are included in sedimentary layers and, more frequently, are found rolled, generally fragmented, and are attributed to the Motuca Formation, of Permian age. The present study aims to carry out the taxonomic and systematic classification of fossil specimens of gymnospermic wood attributed to the Motuca Formation from the Monaf area. The material analyzed corresponds to two fragments of fossil wood, selected based on their good degree of preservation. To analyze the internal morphological characteristics of the specimens, thin petrographic slides were prepared in three wood cutting planes: transverse section, tangential longitudinal and radial longitudinal. From the description of specimens UFT-705 and UFT-882 it was possible to suggest two new morphogenera and morphospecies. Spheroidal and oval coprolites preserved in the pith of specimen UFT-705 were also identified, which are interpreted to have originated from oribatid mites. In this way, the two endemic woods provide additional evidence about biodiversity during the Permian in the Parnaíba Basin. Finally, the presence of coprolites attributed to oribatid mites is another contribution from arthropod-plant interactions.