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The establishment of a segregate lepisoroid fern genus Ellipinema was mainly to accommodate the isolated position of Lepisorus jakonensis (Polypodiaceae) recovered in plastid gene tree. Using newly obtained nuclear data, we recovered that Ellipinema and allied genera, such as Lepidomicrosorium, Lemmaphyllum, Neolepisorus, Paragramma, Tricholepidium and Weatherbya are deeply nested within Lepisorus. The nuclear phylogeny showing incongruent phylogenetic placement in comparison with plastid results perhaps indicated ancient hybridization events. The diagnostic morphology characterizing Ellipinema - elliptic scale-like paraphyses, which is shared by all the taxa of sect. Lepisorus and sect. Hymenophyton - falls within the range of continuous variation in the type species Ellipinema jakonense (=Lepisorus jakonensis). Our study, which integrated molecular and morphological data, demonstrates that the segregation of Ellipinema and ×Ellipisorus (= ×Lepinema Li Bing Zhang & Liang Zhang, nom. illeg.) from Lepisorus should be rejected., (Copyright © 2021 Elsevier Inc. All rights reserved.)

The lady fern genus Athyrium represents one of the most diversified lineages in Athyriaceae with about 160-220 known species, and is notorious for its taxonomic difficulty. Despite progress in recent phylogenetic studies involving this genus, it still lacks a modern systematic and taxonomic update using integrative analyses of molecular and morphological evidence based on a broad species sampling. Here, we present, to our knowledge, the most comprehensive phylogenetic analysis of the genus to date based on a total-evidence approach, covering all formerly accepted segregates within the athyrioid ferns. We sampled up to eight plastid markers and 20 morphological characters for each species. Our analyses, including maximum parsimony, maximum likelihood and Bayesian inference, yield a robust phylogenetic framework. We find that Athyrium is not monophyletic by recovering Athyrium skinneri and A. alpestre nested with Anisocampium and Cornopteris respectively while Pseudocystopteris is included in Athyrium. Furthermore, eight well-resolved clades and two isolated species within Athyrium are found in the phylogenetic topology, which can be also characterized by morphological synapomorphies from traits of petioles, leaves, sori and spores. In the interest of recognizing monophyletic taxa with morphological synapomorphies, we agree with the inclusion of Pseudocystopteris in Athyrium as proposed in previous studies, but treat Anisocampium and Cornopteris as separate genera. We further propose to resurrect a monotypic Pseudathyrium to accommodate A. alpestre. Based on morphological characters and molecular phylogeny, a new infrageneric classification system of Athyrium is proposed which subdivided it into ten sections, and one New-World species A. skinneri is transferred into Anisocampium., (Copyright © 2017 Elsevier Inc. All rights reserved.)

The polygrammoids (Polypodiaceae) are the most species‐rich and diversified epiphytic fern lineages, and hold an important role to understand the deep diverging events and rapid adaptation to changing environments in the plant tree of life. Despite progress in the phylogeny of this group of ferns in previous multilocus phylogenetic studies, uncertainty remains especially in backbone relationships among closely related clades, and the phylogenetic placement of recalcitrant species or lineages. Here, we investigated the deep phylogenetic relationships within Polypodiaceae by sampling all major lineages and using 81 plastid genomes (plastomes), of which 70 plastomes were newly sequenced with high‐throughput sequencing technology. Based on parsimony, maximum‐likelihood, Bayesian and multispecies coalescent analyses of genome skimming data, we achieved a better resolution of the backbone phylogeny of Polypodiaceae. Using simulated data matrices, we detected that potential phylogenetic artefacts, such as long‐branch attraction and insufficient taxonomic sampling, may have a confounding impact on the incongruence of phylogenetic inferences. Furthermore, our phylogenetic analyses offer greater resolution than previous multilocus studies, providing a robust framework for future phylogenetic implications on the subfamilial taxonomy of Polypodiaceae. Our phylogenomic study not only demonstrates the advantage of a character‐rich plastome dataset for resolving the recalcitrant lineages that have undergone rapid radiation, but also sheds new light on integrative explorations understanding the evolutionary history of large fern groups in the genomic era. [ABSTRACT FROM AUTHOR]

The fern genus Lepisorus represents one of the most complicated and controversial lineages in Polypodiaceae, with about 80 species which have been classified into several separate genera, and is notorious for its taxonomic difficulty. Despite progress in recent phylogenetic studies of the family Polypodiaceae involving Lepisorus and its allies, the deep phylogenetic relationship within this group of ferns is still unresolved, and no formal infrageneric classification has been proposed. This contribution presents the most comprehensive phylogenetic analysis of the genus, with 72% species sampled, using a total‐evidence approach based on eight plastid markers and ≤25 morphological characters for each species. The analyses resolve the backbone relationship and yield the most robust phylogenetic framework to date. Congruent with previous studies but with new findings, the results herein show that Lepisorus is monophyletic when Neolepisorus, Lemmaphyllum, Tricholepidium, Neocheiropteris and Lepidomicrosorium are included, as well as Lepisorus jakonensis and Paragramma. Furthermore, 17 well‐resolved clades are found in the phylogenetic topology, which can be characterized by morphological synapomorphies from traits of rhizome scales, laminae, sori and paraphyses. Based on molecular and morphological evidence, a new infrageneric classification system of Lepisorus is proposed which subdivided Lepisorus into 17 sections. [ABSTRACT FROM AUTHOR]