The discovery was made in a lycopsid fossil collected from the Paraná Basin, part of what was once the supercontinent Gondwana. After a detailed reanalysis using advanced imaging techniques, the researchers identified trilete spores embedded within the plant’s original reproductive tissues—an extremely rare state of preservation in rocks from the Permian period.
As reported by University of Vale do Taquari (Univates), which led the study, this is the first record of a lycopsid with in situ spores ever documented in the Paraná Basin. The results not only challenge previous classifications of the fossil but also provide new data to improve the understanding of plant diversity and reproduction in the Permian, before the rise of dinosaurs and the end-Paleozoic mass extinction.
Preserved Spores Offer a Rare Direct Link
The fossil at the center of the study had long been cataloged as Lycopodites riograndensis, but recent investigations revealed much more. With the help of scanning electron microscopy and specialized microfossil recovery protocols, scientists isolated spores still enclosed in the plant’s reproductive structures. These spores, classified as trilete and showing a verrucate surface pattern, matched the characteristics of Converrucosisporites—a palynological genus frequently found in the same strata.
The level of preservation in clastic rocks—dating between 298.9 and 252.17 million years ago—is considered highly uncommon. According to Univates, this in situ occurrence creates a direct biological link that helps bridge the often separate fields of macrofossil and microfossil studies. This connection gives researchers a more integrated look at plant ecosystems during the Permian.
The technique used to isolate the spores was developed at the itt Oceaneon Technological Institute of the University of Vale do Rio dos Sinos (Unisinos). It enabled scientists to extract the reproductive elements without damaging the fossil—a crucial step in confirming their palynological identity.
Taxonomic Overhaul Leads to New Genus
The anatomical and palynological data collected during the study led to a full reclassification of the fossil. The previously assigned genus was deemed inaccurate, prompting the creation of a new one: Franscinella. The fossil now bears the name Franscinella riograndensis, recognizing both its uniqueness and evolutionary relevance.
This taxonomic shift was supported by data published in the Review of Palaeobotany and Palynology, where the researchers outlined the criteria for the new genus. The decision was not just based on the spores, but also on the detailed morphology of the fossil, made accessible through modern analysis.
As explained by lead author Júlia Siqueira Carniere, now a doctoral student at Univates, the discovery was part of her master’s thesis and represents a significant leap in understanding the evolutionary pathways of early vascular plants. The involvement of other institutions, including the Federal University of Rio Grande do Sul (UFRGS) and Germany’s Senckenberg Institute, strengthened the collaborative framework behind the research.
Implications for Permian Plant Research
This is only the fifth known record of herbaceous lycopsids with in situ spores from the Permian of Gondwana. Each such case adds critical information for reconstructing the makeup of prehistoric ecosystems, especially in regions where such data is limited. According to Univates, the Paraná Basin had never yielded this kind of direct fossil-spore association until now.
The finding also contributes to biostratigraphy, a field that uses fossils to determine the relative age of rock layers. By confirming the origin of certain types of spores, researchers can now date layers with greater precision, improving the resolution of the Permian timeline.
Funding for the project was provided by Brazilian science agencies CNPq and CAPES, which supported the interinstitutional effort that brought this 250-million-year-old plant mystery into focus. As noted in the study, the integration of macrofossil and palynological evidence opens up new ways to investigate ancient flora, using both modern technology and reexamined specimens.
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