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Grammitidoideae are the largest subfamily in Polypodiaceae and contain about 911 species. Progress has been made in understanding the overall phylogeny and generic boundaries in the light of recent molecular works. However, the majority of species, especially Asian species, and some critical type species of genera remain unsampled. In this study, a dataset of six plastid markers of 1003 (112 new) accessions representing ca. 412 species of Grammitidoideae including the type species of Ctenopterella, Grammitis, Moranopteris, Radiogrammitis, and Themelium, was assembled to infer a phylogeny. Our major results include: (1) the type species of Grammitis is successfully sequenced using a next‐generation sequencing technique and is resolved in Grammitis s.str. as expected; (2) Ctenopterella is found to be polyphyletic and a new clade consisting of C. khaoluangensis is resolved as sister to Tomophyllum; (3) the type species of Ctenopterella is resolved in a clade sister to the C. lasiostipes clade; (4) Oreogrammitis is found to be polyphyletic and three clades outside of the core Oreogrammitis are identified containing O. subevenosa and allies, O. orientalis, and O. beddomeana (+ O. cf. beddomeana); (5) Prosaptia is found to be paraphyletic with P. nutans being sister to a clade containing the rest of Prosaptia and Archigrammitis; (6) the intergeneric and major relationships within the Asia‐Pacific clade are well resolved and strongly supported except for a few branches; (7) extensive cryptic speciation is detected in the Asia‐Pacific clade; and (8) based on the polyphyly of Ctenopterella we describe three new genera, Boonkerdia, Oxygrammitis, and Rouhania, for species formerly in Ctenopterella; because the type species of Grammitis belongs to Grammitis s.str., we describe five new genera, Aenigmatogrammitis, Grammitastrum (stat. nov.), Howeogrammitis, Nanogrammitis, and Thalassogrammitis for species formerly in Grammitis s.l. A key to the 35 Old‐World genera is given, a taxonomic treatment is presented, and the morphology of all new genera is shown with either a color plate and/or a line drawing. [ABSTRACT FROM AUTHOR]

The infrageneric relationships and taxonomy of the largest fern genus, Asplenium (Aspleniaceae), have remained poorly understood. Previous studies have focused mainly on specific species complexes involving a few or dozens of species only, or have achieved a large taxon sampling but only one plastid marker was used. In the present study, DNA sequences from six plastid markers (atpB, rbcL, rps4, rps4‐trnS, trnL and trnL‐F) of 1030 accessions (616 of them newly sequenced here) representing c. 420 species of Asplenium (60% of estimated species diversity), 16 species of Hymenasplenium, three Diplaziopsidaceae, and four Rhachidosoraceae were used to produce the largest genus‐level phylogeny yet for ferns. Our major results include: (i) Asplenium as broadly circumscribed is monophyletic based on our inclusion of representatives of 32 of 38 named segregate genera; (ii) 11 major clades in Asplenium are identified, and their relationships are mostly well‐resolved and strongly supported; (iii) numerous species, unsampled in previous studies, suggest new relationships and numerous cryptic species and species complexes in Asplenium; and (iv) the accrued molecular evidence provides an essential foundation for further investigations of complex patterns of geographical diversification, speciation and reticulate evolution in this family. [ABSTRACT FROM AUTHOR]

The taxonomy of the cliff fern family Woodsiaceae has been controversial with 22–59 species in 1–7 genera recognized in various classifications. This is mainly due to limited taxon sampling (up to 33 accessions representing up to 21 species) and poor resolution in molecular studies so far. In the present study, DNA sequences of five plastid markers (atpA, matK, rbcL, rps4 + rps4‐trnS, trnL + trnL‐F) of 152 accessions representing ca. 43 out of ca. 65 species estimated of Woodsiaceae (122 accessions), and 30 non‐Woodsiaceae accessions from the most closely related four families (Athyriaceae, Blechnaceae, Onocleaceae, Thelypteridaceae) were used to infer a phylogeny. Our major results include: (1) Woodsiaceae are strongly supported as monophyletic; (2) Two major clades representing the deepest split in Woodsiaceae are identified, corresponding to the two recently proposed subfamilies, Woodsioideae and Protowoodsioideae; (3) Within Woodsioideae and Protowoodsioideae, two and three well‐supported subclades, respectively, are determined; (4) Cheilanthopsis is resolved as paraphyletic in relation to Hymenocystis (sampled for the first time) and Protowoodsia; (5) Physematium and Woodsiopsis are paraphyletic in relation to a clade containing Cheilanthopsis, Hymenocystis, and Protowoodsia; (6) Evolution of 13 morphological characters is inferred in a phylogenetic context, and morphological synapomorphies of each of the five major subclades are identified; (7) We propose to recognize two genera in Woodsiaceae based on deep divergence (ca. 45 Ma), morphology, chromosome number, and geographic distribution: Physematium (syn.: Cheilanthopsis, Hymenocystis, Protowoodsia, Woodsiopsis) and Woodsia (syn.: Eriosoriopsis), and Physematium is further divided into three subgenera and Woodsia into two subgenera; (8) we describe ×Woodsimatium, a hybrid genus (nothogen. nov.) between the two genera recognized. A taxonomic synopsis of the family is provided, and 15 new combinations are made. [ABSTRACT FROM AUTHOR]

[Display omitted] • 169 accessions representing ca. 68 (85% of total) species of Bolbitis are sampled. • Species of Bolbitis are resolved into four major clades. • Six well-supported subclades are identified in the most speciose Asian clade. • Evolution of six characters is analyzed and free venation evolved from anastomosing venation in Bolbitis. • Bolbitis originated from Africa and a dispersal from Asia resulted in continental disjunction between Africa and America. Bolbitis is a pantropical fern genus of Dryopteridaceae with ca. 80 species mainly in tropical Asia. Earlier studies confirmed the monophyly of Bolbitis when Mickelia is excluded and identified three major clades in Bolbitis. However, earlier studies are based on relatively small sampling and the majority of Asian species are not sampled. In this study, DNA sequences of three plastid markers of 169 accessions representing ca. 68 (85 % of total) species of Bolbitis in nine out of the 10 series recognized by Hennipman (1977), and 54 accessions representing the five remaining bolbitidoid genera are used to infer a global phylogeny with a focus on Asian species. The major results include: (1) Bolbitis is strongly supported as monophyletic; (2) species of Bolbitis are resolved into four major clades and their relationships are: the Malagasy/Mascarene clade is sister to the rest, followed by the African clade which is sister to the American clade + the Asian clade; (3) six well-supported subclades are identified in the most speciose Asian clade; (4) the free-veined Egenolfia is embedded in Bolbitis and is paraphyletic in relation to species with anastomosing venation; (5) three series sensu Hennipman (1977), B. ser. Alienae , B. ser. Egenolfianae , and B. ser. Heteroclitae , are paraphyletic or polyphyletic; (6) evolution of six morphological characters is analyzed and free venation is found to have evolved from anastomosing venation and reversed to free venation in Bolbitis ; and (7) biogeographical implications are drawn and it is shown that a single recent dispersal from Asia resulted in continental disjunction of closely related ferns of Bolbitis between Africa and America. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hypodematiaceae are found to be sister to the remaining eupolypods I. • Hypodematium is resolved into seven clades. • A latest Jurassic-earliest Cretaceous origin of the family and an Upper Cretaceous origin of two genera are inferred. • Hypodematium appears to have originated from East Asia and dispersed to Africa and Southeast Asia. • Leucostegia appears to have originated from Southeast Asia and/or East Asia. The Old World fern genera Hypodematium and Leucostegia had long been placed in the families Dryopteridaceae and Davalliaceae, respectively, before the advent of molecular phylogenetics. Recent molecular studies confirmed the recognition of the family Hypodematiaceae composed of these two genera, but the relationships within each of these two genera have been unclear. In the present study we performed phylogenetic analyses (MP, ML, BI) based on DNA data from six plastid markers (atpB , atpB-rbcL , matK , rbcL , rps4 & rps4-trnS , and trnL & trnL-F) of 165 accessions representing 31 species in two genera of Hypodematiaceae as the ingroup and 26 accessions representing Cystopteridaceae, Didymochlaenaceae, Dryopteridaceae, Davalliaceae, Oleandraceae, and Woodsiaceae as the outgroups. Our analyses supported the monophyly of the currently defined Hypodematiaceae only including Hypodematium and Leucostegia and found that the family to be sister to the remaining eupolypods I. Our data resolved three taxa of Leucostegia into two clades. In Hypodematium , 28 taxa are resolved into seven strongly supported clades or single-accession clades. The evolution of important morphological characters are inferred in the phylogenetic context. Our dated phylogeny suggested a latest Jurassic-earliest Cretaceous origin of the family and Upper Cretaceous origin of two genera, with Hypodematiaceae originated from East Asia; extant lineages of Hypodematium originated from East Asia and subsequently into Africa, the Indian region, the Madagascar region, and Southeast Asia; and Leucostegia originated from East Asia and/or Southeast Asia. [ABSTRACT FROM AUTHOR]