ABSTRACT
Four species of lycophytes have been described from the palaeoflora of the Anisian Dont Formation at the Kühwiesenkopf/Monte Prà della Vacca section in the Dolomites (northern Italy); Isoetites brandneri, Lepacyclotes bechstaedtii (both Isoëtaceae), Selaginellites leonardii (Selaginellaceae), and Lycopia dezanchei (order and family indet.). For I. brandneri and S. leonardii, in situ spores have also been reported. We have now restudied in situ material from all four species with a focus on the morphological variability of the spores. Microspores and a single megaspore from L. dezanchei and possible poorly preserved microspores from L. bechstaedtii are described for the first time. The microspores from a paratype of I. brandneri proved to be highly variable and unusual, generally with an elliptical (bilobed) cingulum/zona that resembles the sacci of bisaccate pollen. In addition, both micro- and megaspores from a specimen previously assigned to I. brandneri showed considerable differences to those from the paratype, suggesting a biologically distinct species.
Acknowledgments
Francesca Uzzo, Roberta Branz, Sara Karbacher, and Sally Erkens assisted in the maceration of in situ material. Fridgeir Grimsson (University of Vienna) produced the SEM pictures. We thank the two anonymous reviewers for their helpful suggestions.
Disclosure statement
No potential conflict of interest was reported by the author(s).
Author contributions
HN and EK conceived the study and took samples. EK and JHAVKvC reviewed the macrofossils. HN, EK, and GR reviewed the spores. HN performed analyses, prepared figures, and wrote the paper. All authors read and commented on drafts.
Data availability
The data that support the findings of this study are openly available in Zenodo at https://doi.org/10.5281/zenodo.6426441.