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On the nomenclature of the fossil-genera Acitheca, Bifariusotheca, Polymorphopteris and Strephopteri

by Alexander B. Doweld


The complicated nomenclatural history of the extinct fossil-genera Acitheca and Strephopteris (fertile foliage) and Polymorphopteris (sterile foliage), established for fossil ferns (Marattiopsida), is reviewed and corrected with new bibliographic and historical data. Strephopteris as a generic name established for fertile foliage of Acitheca-type has a priority, but due to the long and widespread use of Acitheca it was recently proposed to reject it in favour of the established name Acitheca. Since Acitheca as a fossil-genus was established for distinctive fertile foliage, but its currently accepted type species, A. polymorpha (≡ Pecopteris polymorpha) was founded on the sterile foliage, it is proposed to reject this type and return to the earlier concept of Sterzel who thought that Acitheca was typified by the fossil-species Scolecopteris conspicua, based on fertile foliage. This procedure requires official conservation of the type species. This correction of the type species allows continuing the current use of another fossil-genus Polymorphopteris, which was inadvertently validated on the same type species as Acitheca. The legitimization of the fossil-genus Polymorphopteris, based on sterile foliage only, will stabilize the current established systematics of fossil marattiopsid remains, for which no fertile organs are known. Since S. conspicua, when established as a fertile counterpart of sterile foliage known as Pecopteris polymorpha, originally included two unrelated types of fertile foliage, known as compressions and petrifactions, the typification of the fossil-species by fossil specimens known as compressions allows continued use of Acitheca as a distinct fossil-genus for fertile foliage as compressions. The petrifactions formerly attributed to A. polymorpha from the younger sediments (Lower Permian) of France are re-considered as a distinct fossil-species, Scolecopteris renaultii sp. nov. The formerly invalidly published fossil- genus Bifariusotheca for Acitheca-like fossils from the Permian of China is validated. Kamatheca is validated for the aberrant Angaridan fossil-species, Acitheca gigantea. Nine invalidly published fossil-species of Polymorphopteris are validated to follow modern circumscription of the fossil-genus: Polymorphopteris cistii comb. nov., P. gothanii comb. nov., P. integra comb. nov., P. magdalenae sp. nov., P. multifurcata comb. nov., P. oblongifolia comb. nov., P. pseudobucklandii comb. nov., P. pseudointegra comb. nov., and P. wagneri Doweld, sp. nov. Scolecopteris conspicua is neotypified, Pecopteris cistii is lectotypified. As an addition to Taxonomic Literature II records, the precise dates of publication of the taxonomic works of Germar’s Versteinerungen (1844–1853) and Schimper & Schenk’s Palaeophytologie (1879–1890) are established for the first time.



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