Fern and Lycophyte Evolution Lab

Abstract: The genus Pleopeltis stands out for its high species richness in tropical montane regions and its disjunct neotropical–afrotropical distribution, with most species occurring in the Neotropics. This distribution provides a unique opportunity to explore dispersal patterns, a key mechanism in fern biogeography. In this study, we aimed to identify the biogeographic processes shaping the distribution of Pleopeltis and the directionality of its dispersal events throughout evolutionary history. We analysed a combined dataset of three plastid regions from 70 species to infer divergence times. Ancestral range estimation and stochastic biogeographic mapping were used to elucidate biogeographic patterns and processes. Our findings showed that dispersal was the main process driving the genus’s distribution, accounting for nearly half of the inferred biogeographic events. Notably, we identified a recent west-to-east dispersal pattern connecting the Neotropics with the Paleotropics, highlighting the significance of long-distance dispersal in ferns. Mexico and Central America were identified as the centre of origin and diversity for the genus and the main source of dispersal. The Andes were the second most important centre, functioning as a source and sink for dispersal events. These findings emphasize the critical roles of these dynamic centres in the diversification and distribution of global biodiversity.

Abstract: Test the floristic structure of fern and lycophyte in the Northeastern Atlantic Forest based on the two sub-regions of endemism, (1) montane inland wet forests and (2) Coastal Forests. Northeastern Brazil's Atlantic Forest, particularly the Coastal and Montane inland wet forests. Floristic composition was compiled from GBIF data, and environmental data were extracted from rasters for 57 forest remnants. PCA analyses were carried out to assess environmental structuring, NMDS to test floristic dissimilarity, and generalised dissimilarity modelling (GDM) to examine environmental effects on community distribution. Clusters were formed by K-means, and statistical analyses such as PERMANOVA and ANOSIM were carried out to test the significance of the results. A total of 307 species were recorded, 93.2% of which were ferns and 6.8% lycophytes. The floristic composition showed 71.6% of species shared between both sub-regions. PCA displayed significant environmental differences between montane inland wet forests and coastal forests, but NMDS did not indicate any separation in floristic composition. However, the clusters identified by K-means were highly significant (R = 0.445), in contrast to the groupings of the sub-regions (R = 0.124). GDM explained 78.8% of the distribution pattern, and its cluster classification revealed no clear structure between NAF sub-regions. Additionally, GDM highlighted variables such as geographic distance, cloud cover, rainfall, silt content and soil pH as determinants of the communities. Despite differences in environmental factors between montane inland wet forests and coastal forests, the floristic composition of ferns and lycophytes does not reflect this separation, suggesting that historical biogeography and long-distance dispersal facilitate high connectivity between these sub-regions.

Abstract: This study presents the second record of Metania kiliani (Porifera: Metaniidae) three decades after its description in 1992. The sponge was found on a herbarium specimen of the terrestrial fern Actinostachys pennula (Schizaeaceae), which is typically known to be absent from flooded environments. As sponges need at least some weeks to establish themselves on a support, this first record of a freshwater sponge on this fern suggests that A. pennula can withstand prolonged submergence. This is the first record of M. kiliani for the state of Roraima, Brazil.

Abstract: The present study contributes to the knowledge of the fern and lycophyte flora of the city of Chapadinha, an area of the Cerrado located in the eastern state of Maranhão, Brazil. The study also presents taxonomic and environmental data on the occurrence of these species. Species were collected during five expeditions performed between December 2021 and August 2022, in two protected areas and some sites associated with wet environments outside these areas. In addition, specimens deposited in an herbarium were examined. In total, 20 species of ferns and three species of lycophytes were recorded, distributed over 12 families and 16 genera. The most representative families were Pteridaceae (six species) and Thelypteridaceae (four species). Despite the anthropization, riparian forests showed the highest richness (21 species), among which the non-flooded riparian forests stood out (18 species). Our data highlight the importance of identifying fern and lycophyte species and emphasize the potential of these species in future conservation studies and as ecological bioindicators.

Abstract: We discuss the importance of fern and lycophyte species in the Atlantic Forest ecosystem as well as the need for floristic inventories to understand their distribution and conservation status. We focus on the Serra do Papagaio region in southeastern Brazil, which is known for its high plant diversity but lacks comprehensive inventories of ferns and lycophytes. In this study, we conducted a floristic inventory of Serra do Papagaio and identified 172 fern and 29 lycophyte species. Our findings reveal 21 threatened species and two new records for Minas Gerais State. Additionally, we compared the floristic composition of Serra do Papagaio with that of other areas within the Atlantic Forest using non-metric multidimensional scaling (NMDS) and generalized dissimilarity modeling (GDM) analyses. The results highlight distinct clusters of areas based on elevation and geographic location. We emphasize the need for further sampling and conservation efforts in Serra do Papagaio as well as provide valuable insights into the drivers of fern and lycophyte diversity in the Atlantic Forest.

Abstract: Gleicheniaceae is an early diverging lineage of leptosporangiate ferns. Although the family can be readily recognized by the pseudodichotomousbranching pattern of its fronds, generic circumscription has long been debated. Phylogenetic analyses based on genomic data supported themonophyly of six genera (Dicranopteris, Diplopterygium, Gleichenella, Gleichenia, Rouxopteris, and Stromatopteris) but indicate the paraphylyof Sticherus. To accommodate this latter result, we describe a new genus, Sticheropsis, gen. nov., segregated from Sticherus. We provide a newtaxonomic treatment of Gleicheniaceae, including an identification key to all eight genera, descriptions of the genera with comments and notesconcerning geographic distributions and phylogenetic affinities, as well as an overview of the morphology of the family with a revised and uni-fied terminology for the fronds. We recognize 149 species plus two hybrids for the family, distributed into eight genera, and propose six newcombinations.