Cretaceous diversity of Schizaeales in Antarctica, <i>Escuderia livingstonensis</i> gen. et sp. nov., a permineralized fertile organ from Livingston Island, and its ecological implications combined with associated biota

The new genus Escuderia differs from both extant taxa and previously known fossil forms, exhibiting a primitive branching pattern and other anatomical features that provide new evidence for reconstructing the evolutionary history of the Schizaeales. The finding strengthens the hypothesis that Antarctica may have played a significant role in the diversification of the Schizaeales as well as of other leptosporangiate ferns. This study serves as a starting point for future comprehensive phylogenetic analyses of the Schizaeales, including undescribed permineralized fossils recently discovered in Japan and southern South America.