Taxonomy and nomenclature ofSphenopterisand allied fossil‐genera of Carboniferous seed‐plant fronds

Abstract

AbstractMost remains of Carboniferous lyginopteridalean seed‐plant fronds used to be classified in a single fossil‐genus (Sphenopteris) based mainly on pinnule morphology. By incorporating additional characters linked to frond architecture and rachial features a more natural taxonomy has now been achieved. Eight fossil‐genera of lyginopteridalean fronds are now recognised (Sphenopteris,Calymmotheca,Eusphenopteris,Karinopteris,Mariopteris,Palmatopteris,Spathulopteris,Sphenopteridium) for which the diagnostic descriptions, nomenclatural types and stratigraphical/chronological distribution are clarified. This provides a more natural and therefore robust means of recording these fossils, which will help improve studies on past plant diversity and floristics. A by‐product of this revision is that some fossil‐species of fern fronds previously placed inSphenopteriswill need to be reclassified into fossil‐genera that are defined on reproductive structures.