Revision of Ilfeldia and establishment of Ovulepteris gen. nov. from the Pennsylvanian of Europe, with a discussion on their concepts

This paper presents a taxonomic revision of the fossil-genus Ilfeldia Remy and establishes the fossil-genus Ovulepteris nov. Three species of Ilfeldia (Ilfeldia jejunata, Ilfeldia gregoriensis nov. sp. and Ilfeldia polysporangiata comb. nov.) have been identified in Europe from localities in the Douro Basin (Portugal), Ilfeld Basin (Germany) and at Manebach (Germany). The stratigraphic distribution of the fossil-genus varies from Gzhelian (Carboniferous) (I. jejunata and I. gregoriensis sp. nov.) to lower Asselian (Permian) (I. polysporangiata comb. nov.). All species of Ilfeldia are associated with larger taeniopterid leaves that could potentially be sterile equivalents due to dimorphism, and sterile and fertile leaves have been found in organic connection in I. gregoriensis sp. nov. Ilfeldia may be affiliated with the ferns or pteridosperms, but the systematic position is unclear. Ovulepteris gen. nov., which is established for leaves that bear ovule-type reproductive organs, has oblong leaves with a partly reduced leaf lamina, with reproductive organs situated on the leaf margin. The concept of Ovulepteris gen. nov. is based on material originally described by Obrhel (1957, 1965) under the names Ilfeldia robusta Obrhel and Ilfeldia lobecensis Obrhel from the Pennsylvanian of the Czech Republic. The new combinations Ovulepteris robusta (Obrhel) comb. nov. and Ovulepteris lobecensis (Obrhel) comb. nov. are established herein. Ovulepteris gen. nov. differs from Sobernheimia in the style of placement of the seeds. In Ovulepteris gen. nov., seeds are situated at the end of veins in protruding segments, whereas their attachment in Sobernheimia is uncertain but appear to be attached to the “midrib”. The diagnosis of Ovulepteris gen. nov. is not identical with the diagnoses of existing genera that have leaves with ovules, necessitating establishment of this new fossil-genus. The systematic position of all fossil-genera studied herein is uncertain, although they appear to be a member of the pteridosperms.