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Premise of research. The Río Genoa Formation of Argentine Patagonia hosts Early Permian fossil assemblages that document levels of plant diversity rare among coeval floras. Ongoing work to exhaustively characterize the diversity of these assemblages is key to understanding Permian vegetation and plant evolution. A new fern type identified in the Río Genoa Formation exhibits a novel combination of characters that required taxonomic assessment. Methodology. Observations and measurements of vegetative and reproductive morphology of compression fossils were used in a comparative framework to address the taxonomic placement of the fossils. Pivotal results. The new fern, Floratheca apokalyptika gen. et sp. nov., is characterized by small pinnules with a free base, weakly lobed margin, highly decurrent midvein, and rarely branched lateral veins, as well as radially symmetrical synangia with stellate dehiscence, consisting of six spindle-shaped sporangia. This unique combination of characters distinguishes Floratheca from the more than 25 Permo-Carboniferous marattialean genera known from compressions. Floratheca exhibits variable synangium morphology during development and variation in pinnule base morphology due to a combination of adaxial-abaxial asymmetry of ultimate rachises and taphonomic effects. Conclusions. Floratheca is one of only three late Paleozoic bona fide marattialean compression genera endemic to Gondwana and the second late Paleozoic endemic South American marattialean with preserved fertile structures. Floratheca adds to an increasing diversity of fossils that diminish the disparity between the Southern and Northern Hemispheres, in terms of the extent and intensity of exploration of the plant fossil record, currently skewed taxonomically toward Northern Hemisphere taxa. Variability of synangium and pinnule base morphology in Floratheca cautions against potential taxonomic inflation produced by establishment of new taxa based on small numbers of specimens and incomplete understanding of development and taphonomy. [ABSTRACT FROM AUTHOR]

Reflectance Transforming Imaging (RTI) produces photographs in which the angle of the light can be changed at will, allowing to investigate remotely minute details of the 3D structure of sub-planar objects. Here we apply this technique to the type specimen of Gingkophyllum grassetii , a vegetative shoot with putative ginkgophyte affinities from the early Permian of Lodève (France). Gingkophyllum grassetii , the type species of the genus, was originally described by Saporta in 1875 and has never been illustrated other than by drawings representing only portions of the shoot. Using RTI, we describe and illustrate the specimen and discuss some key features, such as the arrangement of the leaves on the shoot or the presence of abundant secretory structures. Through an historical account, we show how the lack of illustration led to confusion about the morphology of Ginkgophyllum and we discuss the importance of reinvestigating type specimens of Paleozoic ginkgophyte taxa in order to clarify their taxonomy and better understand their evolutionary history. The sharing of RTI files is one example of approaches that can be further developed to improve remote access to specimens. • Ginkgophyllum grassetii , the type species of the genus, is a putative Permian ginkgophyte. • Lack of published photos led to confusions about Ginkgophyllum morphology and taxonomy. • We re-investigate the type specimen using Reflectance Transforming Imaging. • We provide new information on the morpho-anatomy of the specimen. • RTI files could be further used to improve remote access to collection specimens. [ABSTRACT FROM AUTHOR]