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  1. Abstract Parablechnumis the most diverse genus in the fern family Blechnaceae, with about 70 species, mainly from Central and South America, the Austropacific, and a few in Africa. Species delimitation inParablechnumis challenging, and regional studies vary in species recognized. This genus is generally found in humid mid- to high-elevation forests, especially in the Andes. Ecuador is notable for its high species richness, particularly in the poorly explored Cordillera del Cóndor, a sub-Andean range with a distinctive geology contributing to high plant diversity and endemism. Since the early 2000s, botanical expeditions have revealed numerous endemic species, highlighting the region's significance. In 2006, an unusualParablechnumspecies was collected in the Cordillera del Cóndor. Here, we describe it as a new species,Parablechnum shuariorum. It grows on sandstone cliffs along small rivers and can be distinguished by its fertile fronds, which are shorter than its sterile ones, and its densely scaly rachis. This species, endemic to the Cordillera del Cóndor, is found at elevations of 900–1,600 m. It is named after the Shuar people, whose lands include the collection sites. Preliminary conservation assessment suggests thatP. shuariorumis endangered due to a limited area of occupancy and threats from human activities, such as mining. 
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    Free, publicly-accessible full text available March 1, 2026
  2. Abstract PremiseReticulate evolution, often accompanied by polyploidy, is prevalent in plants, and particularly in the ferns. Resolving the resulting non‐bifurcating histories remains a major challenge for plant phylogenetics. Here, we present a phylogenomic investigation into the complex evolutionary history of the vining ferns,Lygodium(Lygodiaceae, Schizaeales). MethodsUsing a targeted enrichment approach with theGoFlag 408flagellate land plant probe set, we generated large nuclear and plastid sequence datasets for nearly all taxa in the genus and constructed the most comprehensive phylogeny of the family to date using concatenated maximum likelihood and coalescence approaches. We integrated this phylogeny with cytological and spore data to explore karyotype evolution and generate hypotheses about the origins of putative polyploids and hybrids. ResultsOur data and analyses support the origins of several putative allopolyploids (e.g.,L. cubense, L. heterodoxum) and hybrids (e.g.,L.×fayae) and also highlight the potential prevalence of autopolyploidy in this clade (e.g.,L. articulatum, L. flexuosum, andL. longifolium). ConclusionsOur robust phylogenetic framework provides valuable insights into dynamic reticulate evolution in this clade and demonstrates the utility of target‐capture data for resolving these complex relationships. 
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  3. The name Parablechnum christii (C. Chr.) Gasper & Salino has been applied to a small species with few pairs of short pinnae that is endemic to Costa Rica and Panama. After reviewing type material of this name, we conclude that it has been misapplied and is, in fact, a synonym of P. falciforme (Liebm.) Gasper & Salino, an older name. Because the specimens previously identified as P. christii lack a name, we propose P. talamancanum S. Molino & R. C. Moran for these plants. The species is endemic to the mountains of Costa Rica and Panama, from 1200 to 3350 m. 
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  4. Abstract—Goniopteris×tico, a new hybrid fern from La Selva Biological Station in Heredia Province, Costa Rica, is described based on morphology and analysis of target-capture DNA sequence data. The hybrid co-occurs with its two putative progenitors,Goniopteris mollisandGoniopteris nicaraguensis,and is readily recognizable by its intermediate leaf dissection and venation. It is also intermediate in pinnae size and shape, and presents irregularly lobed pinnae. Despite the broad overlap in the geographic distribution of its parental taxa,Goniopteris×ticois only known from two collections from a single area of the La Selva Biological Station, highlighting the importance of close observation of ferns from even well-collected areas. 
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  5. Resumen Se presenta una actualización a la flora de Antioquia, Colombia paraSelaginella.Se reconocen 46 especies, 12 de las cuales son nuevos registros para el departamento, incluyendo dos especies recientemente descritas (S. gioiaeyS. rachipterygia), una especie no descrita y un nuevo registro para el país (S. meridensis). Cinco especies previamente reportadas para Antioquia se excluyen. Se presenta una clave dicotómica y notas sobre la distribución para las 46 especies reconocidas. 
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  6. Abstract PremisePteridophytes—vascular land plants that disperse by spores—are a powerful system for studying plant evolution, particularly with respect to the impact of abiotic factors on evolutionary trajectories through deep time. However, our ability to use pteridophytes to investigate such questions—or to capitalize on the ecological and conservation‐related applications of the group—has been impaired by the relative isolation of the neo‐ and paleobotanical research communities and by the absence of large‐scale biodiversity data sources. MethodsHere we present the Pteridophyte Collections Consortium (PCC), an interdisciplinary community uniting neo‐ and paleobotanists, and the associated PteridoPortal, a publicly accessible online portal that serves over three million pteridophyte records, including herbarium specimens, paleontological museum specimens, and iNaturalist observations. We demonstrate the utility of the PteridoPortal through discussion of three example PteridoPortal‐enabled research projects. ResultsThe data within the PteridoPortal are global in scope and are queryable in a flexible manner. The PteridoPortal contains a taxonomic thesaurus (a digital version of a Linnaean classification) that includes both extant and extinct pteridophytes in a common phylogenetic framework. The PteridoPortal allows applications such as greatly accelerated classic floristics, entirely new “next‐generation” floristic approaches, and the study of environmentally mediated evolution of functional morphology across deep time. DiscussionThe PCC and PteridoPortal provide a comprehensive resource enabling novel research into plant evolution, ecology, and conservation across deep time, facilitating rapid floristic analyses and other biodiversity‐related investigations, and providing new opportunities for education and community engagement. 
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    Free, publicly-accessible full text available March 10, 2026
  7. BACKGROUND Madagascar is one of the world’s foremost biodiversity hotspots. Its unique assemblage of plants, animals, and fungi—the majority of which evolved on the island and occur nowhere else—is both diverse and threatened. After human arrival, the island’s entire megafauna became extinct, and large portions of the current flora and fauna may be on track for a similar fate. Conditions for the long-term survival of many Malagasy species are not currently met because of multiple anthropogenic threats. ADVANCES We review the extinction risk and threats to biodiversity in Madagascar, using available international assessment data as well as a machine learning analysis to predict the extinction risks and threats to plant species lacking assessments. Our compilation of global International Union for Conservation of Nature (IUCN) Red List assessments shows that overexploitation alongside unsustainable agricultural practices affect 62.1 and 56.8% of vertebrate species, respectively, and each affects nearly 90% of all plant species. Other threats have a relatively minor effect today but are expected to increase in coming decades. Because only one-third (4652) of all Malagasy plant species have been formally assessed, we carried out a neural network analysis to predict the putative status and threats for 5887 unassessed species and to evaluate biases in current assessments. The percentage of plant species currently assessed as under threat is probably representative of actual numbers, except in the case of the ferns and lycophytes, where significantly more species are estimated to be threatened. We find that Madagascar is home to a disproportionately high number of Evolutionarily Distinct and Globally Endangered (EDGE) species. This further highlights the urgency for evidence-based and effective in situ and ex situ conservation. Despite these alarming statistics and trends, we find that 10.4% of Madagascar’s land area is protected and that the network of protected areas (PAs) covers at least part of the range of 97.1% of terrestrial and freshwater vertebrates with known distributions (amphibians, freshwater fishes, reptiles, birds, and mammal species combined) and 67.7% of plant species (for threatened species, the percentages are 97.7% for vertebrates and 79.6% for plants). Complementary to this, ex situ collections hold 18% of vertebrate species and 23% of plant species. Nonetheless, there are still many threatened species that do not occur within PAs and are absent from ex situ collections, including one amphibian, three mammals, and seven reptiles, as well as 559 plants and more yet to be assessed. Based on our updated vegetation map, we find that the current PA network provides good coverage of the major habitats, particularly mangroves, spiny forest, humid forest, and tapia, but subhumid forest and grassland-woodland mosaic have very low areas under protection (5.7 and 1.8% respectively). OUTLOOK Madagascar is among the world’s poorest countries, and its biodiversity is a key resource for the sustainable future and well-being of its citizens. Current threats to Madagascar’s biodiversity are deeply rooted in historical and present social contexts, including widespread inequalities. We therefore propose five opportunities for action to further conservation in a just and equitable way. First, investment in conservation and restoration must be based on evidence and effectiveness and be tailored to meet future challenges through inclusive solutions. Second, expanded biodiversity monitoring, including increased dataset production and availability, is key. Third, improving the effectiveness of existing PAs—for example through community engagement, training, and income opportunities—is more important than creating new ones. Fourth, conservation and restoration should not focus solely on the PA network but should also include the surrounding landscapes and communities. And finally, conservation actions must address the root causes of biodiversity loss, including poverty and food insecurity. In the eyes of much of the world, Madagascar’s biodiversity is a unique global asset that needs saving; in the daily lives of many of the Malagasy people, it is a rapidly diminishing source of the most basic needs for subsistence. Protecting Madagascar’s biodiversity while promoting social development for its people is a matter of the utmost urgency Visual representation of five key opportunities for conserving and restoring Madagascar’s rapidly declining biodiversity identified in this Review. The dashed lines point to representative vegetation types where these recommendations could have tangible effects, but the opportunities are applicable across Madagascar. ILLUSTRATION: INESSA VOET 
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  8. BACKGROUND The Republic of Madagascar is home to a unique assemblage of taxa and a diverse set of ecosystems. These high levels of diversity have arisen over millions of years through complex processes of speciation and extinction. Understanding this extraordinary diversity is crucial for highlighting its global importance and guiding urgent conservation efforts. However, despite the detailed knowledge that exists on some taxonomic groups, there are large knowledge gaps that remain to be filled. ADVANCES Our comprehensive analysis of major taxonomic groups in Madagascar summarizes information on the origin and evolution of terrestrial and freshwater biota, current species richness and endemism, and the utilization of this biodiversity by humans. The depth and breadth of Madagascar’s biodiversity—the product of millions of years of evolution in relative isolation —is still being uncovered. We report a recent acceleration in the scientific description of species but many remain relatively unknown, particularly fungi and most invertebrates. DIGITIZATION Digitization efforts are already increasing the resolution of species richness patterns and we highlight the crucial role of field- and collections-based research for advancing biodiversity knowledge in Madagascar. Phylogenetic diversity patterns mirror that of species richness and endemism in most of the analyzed groups. Among the new data presented, our update on plant numbers estimates 11,516 described vascular plant species native to Madagascar, of which 82% are endemic, in addition to 1215 bryophyte species, of which 28% are endemic. Humid forests are highlighted as centers of diversity because of their role as refugia and centers of recent and rapid radiations, but the distinct endemism of other areas such as the grassland-woodland mosaic of the Central Highlands and the spiny forest of the southwest is also important despite lower species richness. Endemism in Malagasy fungi remains poorly known given the lack of data on the total diversity and global distribution of species. However, our analysis has shown that ~75% of the fungal species detected by environmental sequencing have not been reported as occurring outside of Madagascar. Among the 1314 species of native terrestrial and freshwater vertebrates, levels of endemism are extremely high (90% overall)—all native nonflying terrestrial mammals and native amphibians are found nowhere else on Earth; further, 56% of the island’s birds, 81% of freshwater fishes, 95% of mammals, and 98% of reptile species are endemic. Little is known about endemism in insects, but data from the few well-studied groups on the island suggest that it is similarly high. The uses of Malagasy species are many, with much potential for the uncovering of useful traits for food, medicine, and climate mitigation. OUTLOOK Considerable work remains to be done to fully characterize Madagascar’s biodiversity and evolutionary history. The multitudes of known and potential uses of Malagasy species reported here, in conjunction with the inherent value of this unique and biodiverse region, reinforce the importance of conserving this unique biota in the face of major threats such as habitat loss and overexploitation. The gathering and analysis of data on Madagascar’s remarkable biota must continue and accelerate if we are to safeguard this unique and highly threatened subset of Earth’s biodiversity. Emergence and composition of Madagascar’s extraordinary biodiversity. Madagascar’s biota is the result of over 160 million years of evolution, mostly in geographic isolation, combined with sporadic long distance immigration events and local extinctions. (Left) We show the age of the oldest endemic Malagasy clade for major groups (from bottom to top): arthropods, bony fishes, reptiles, flatworms, birds, amphibians, flowering plants, mammals, non-flowering vascular plants, and mollusks). Humans arrived recently, some 10,000 to 2000 years (top right) and have directly or indirectly caused multiple extinctions (including hippopotamus, elephant birds, giant tortoises, and giant lemurs) and introduced many new species (such as dogs, zebu, rats, African bushpigs, goats, sheep, rice). Endemism is extremely high and unevenly distributed across the island (the heat map depicts Malagasy palm diversity, a group characteristic of the diverse humid forest). Human use of biodiversity is widespread, including 1916 plant species with reported uses. The scientific description of Malagasy biodiversity has accelerated greatly in recent years (bottom right), yet the diversity and evolution of many groups remain practically unknown, and many discoveries await. 
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  9. Summary Lycopodiaceae are one of three surviving families of lycopsids, a lineage of vascular plants with a fossil history dating to at least the Early Devonian or perhaps the Late Silurian (c. 415 Ma). Many fossils have been linked to crown Lycopodiaceae, but the lack of well‐preserved material has hindered definitive recognition of this group in the paleobotanical record.New, exceptionally well‐preserved permineralized lycopsid fossils from the Early Cretaceous (125.6 ± 1.0 Ma) of Inner Mongolia, China, were examined in detail using acetate peel and micro‐computed tomography techniques. The anatomy of extant Lycopodiaceae was analyzed for comparison using fluorescence microscopy. Phylogenetic relationships of the new fossil to extant Lycopodiaceae were evaluated using parsimony and maximum likelihood analyses.Lycopodicaulis oellgaardiigen. et sp. nov. provides the earliest unequivocal and best‐documented evidence of crown Lycopodiaceae and Lycopodioideae, based on anatomically‐preserved fossil material.Recognition ofLycopodicaulisin Asia during the Early Cretaceous indicates the presence of crown Lycopodiaceae at this time, and striking similarities of stem anatomy with extant species provide a framework for the understanding of the interaction of branching and vascular anatomy in crown‐group lycopsids. 
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