El perfil del cerro Mudadero y su flora fósil. Provincia de La Rioja, Argentina

The survey of a section more than 500 m thick in the Mudadero Hill (West of Jague) made possible the recognition of six litofacies and the collection of an important number of Lower Carboniferous fossil plants. Five taxa have been identified: Frenguellia exinzia (Frenguelli) Arrondo, Cesari & Gutierrez; Malanznnia ottonei SP. nov.; Diplothmema bodenbenderi (Kurtz) Cesari; Eusphenopteris devonica (Frenguelli) Sessarego & Cesari and ?Oclloa sp. Their study and the analysis of the litofacies show the palaeoenvironmental evolution of the sequence with clear marine activity in its lower section, followed by the characteristic of lagoonal sedimentation up to a progressive continentalization in its upper part. A distribution chart shows thirteen species of the Early Carboniferous in Argentina, disu•ibuted in seven localities. The bolson of Jague has the richest paleofloristic association