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Dryopteris jinpingensis, a new species of diploid, sexually reproductive ferns of Dryopteridaceae from Yunnan, southwestern China, is described and illustrated. Morphologically, D. jinpingensis is similar to D. gaoligongensis but unique in elongated lanceolate laminae, sessile or subsessile pinna stalks, and overlapping membranous scales adnate to stipe base. Phylogenetic analyses based on both plastome and the nuclear AK1 gene sequences showed that D. jinpingensis is sister to D. gaoligongensis. A detailed taxonomic description with line drawings is provided, and its conservation status is evaluated to be critically endangered.

Primulina jiulianshanensis F.Wen & G.L.Xu, a new species of Gesneriaceae from Jiulianshan National Nature Reserve of Jiangxi Province, China, is described and illustrated here. Molecular evidence showed it was sister to P. wenii Jian Li & L.J.Yan, while the morphological observation found clear differences between them, petiole, both sides of leaf blades, adaxial surface of the calyx lobes, corolla inside toward the bottom, bract margins covered glandular-pubescent hairs in P. jiulianshanensis (vs. no glandular-pubescent hairs in P. wenii); lateral bracts 4–9 × ca. 2 mm, the central one 2–5 × 1–1.5 mm, adaxially glabrous but sparsely pubescent at apex (vs. lateral bracts 14–16 × 2.5–3.0 mm, the central one 10–12 × 1.3–1.6 mm, all adaxially pubescent); calyx lobes 8–11 × ca. 2 mm, each side with several brown serrate teeth at apex (vs. 14–15 × ca. 2.5 mm, margin entire); filaments and staminodes sparsely yellow glandular-puberulent (vs. white, glabrous).

Abstract Background Polypodiales suborder Dennstaedtiineae contain a single family Dennstaedtiaceae, eleven genera, and about 270 species, and include some groups that were previously placed in Dennstaedtiaceae, Hypolepidaceae, Monachosoraceae, and Pteridaceae. The classification and phylogenetic relationships among these eleven genera have been poorly understood. To explore the deep relationships within suborder Dennstaedtiineae and estimate the early diversification of this morphologically heterogeneous group, we analyzed complete plastomes of 57 samples representing all eleven genera of suborder Dennstaedtiineae using maximum likelihood and Bayesian inference. Results The phylogenetic relationships of all the lineages in the bracken fern family Dennstaedtiaceae were well resolved with strong support values. All six genera of Hypolepidoideae were recovered as forming a monophyletic group with full support, and Pteridium was fully supported as sister to all the other genera in Hypolepidoideae. Dennstaedtioideae (Dennstaedtia s.l.) fell into four clades with full support: the Microlepia clade, the northern Dennstaedtia clade, the Dennstaedtia globulifera clade, and the Dennstaedtia s.s. clade. Monachosorum was strongly resolved as sister to all the remaining genera of suborder Dennstaedtiineae. Based on the well resolved relationships among genera, the divergence between Monachosorum and other groups of suborder Dennstaedtiineae was estimated to have occurred in the Early Cretaceous, and all extant genera (and clades) in Dennstaedtiineae, were inferred to have diversified since the Late Oligocene. Conclusion This study supports reinstating a previously published family Monachosoraceae as a segregate from Dennstaedtiaceae, based on unique morphological evidence, the shady habitat, and the deep evolutionary divergence from its closest relatives.

The fern species Tectaria fuscipes and morphologically similar species, which are common in tropical and subtropical mainland Asia, constitute a taxonomically confusing group. To better understand species boundaries and relationships within the T. fuscipes group, we conducted phylogenetic analyses of five plastid regions and morphological observations of herbarium specimens and living plants. As a result, we produced a generally well-resolved phylogeny of the T. fuscipes group and related species in Asia. The phylogenetic analyses supported the monophyly of the T. fuscipes group, which includes T. dissecta, T. fuscipes, T. ingens, T. paradoxa, T. setulosa, T. subfuscipes, T. subsageniacea and a new species, but excludes T. kusukusensis. However, T. fuscipes, T. subfuscipes and T. subsageniacea are almost indistinguishable in morphology, which form a complex characterised by the black linear-lanceolate stipe scales. The new species found in southern China and Vietnam is described here as T. fungii. It is similar to the T. fuscipes complex and T. kusukusensis, but differs from the former mainly by its brown-castaneous lanceolate stipe scales and from the latter by having nearly hairless laminae (versus frond axes abaxially bearing copious hairs).

Dryopteris sect. Diclisodon is a small section of ferns with about 12 species mainly distributed in East Asia. Here, we carried out morphological and phylogenetic analyses of this section. A new species from southwest China, D. gaoligongensis, is described and illustrated. Dryopteris gaoligongensis resembles D. indonesiana and D. sparsa, but differs by having a creeping rhizome and large 4-pinnate fronds. We also show that D. glabrior Ching & Z.Y. Liu is a distinct species; however, because it is a later homonym of D. glabrior Copel., it should be renamed D. renchangiana. We conclude that a species previously known as D. nitidula, also an illegitimate homonym, should be recognized with a new name, D. sinonepalensis. We resolve the phylogenetic position of D. yoroii as sister to other sampled species of D. sect. Diclisodon. Our phylogenetic analyses confirm the distinctiveness of D. gaoligongensis, D. renchangiana, and D. sinonepalensis. A key to species of D. sect. Diclisodon in China is provided.

Structural variation of plastid genomes (plastomes), particularly large inversions and gene losses, can provide key evidence for the deep phylogeny of plants. In this study, we investigated the structural variation of fern plastomes in a phylogenetic context. A total of 127 plastomes representing all 50 recognized families and 11 orders of ferns were sampled, making it the most comprehensive plastomic analysis of fern lineages to date. The samples included 42 novel plastomes of 15 families with a focus on Hymenophyllales and Gleicheniales. We reconstructed a well-supported phylogeny of all extant fern families, detected significant structural synapomorphies, including 9 large inversions, 7 invert repeat region (IR) boundary shifts, 10 protein-coding gene losses, 7 tRNA gene losses or anticodon changes, and 19 codon indels (insertions or deletions) across the deep phylogeny of ferns, particularly on the backbone nodes. The newly identified inversion V5, together with the newly inferred expansion of the IR boundary R5, can be identified as a synapomorphy of a clade composed of Dipteridaceae, Matoniaceae, Schizaeales, and the core leptosporangiates, while a unique inversion V4, together with an expansion of the IR boundary R4, was verified as a synapomorphy of Gleicheniaceae. This structural evidence is in support of our phylogenetic inference, thus providing key insight into the paraphyly of Gleicheniales. The inversions of V5 and V7 together filled the crucial gap regarding how the “reversed” gene orientation in the IR region characterized by most extant ferns (Schizaeales and the core leptosporangiates) evolved from the inferred ancestral type as retained in Equisetales and Osmundales. The tRNA genes trnR-ACG and trnM-CAU were assumed to be relicts of the early-divergent fern lineages but intact in most Polypodiales, particularly in eupolypods; and the loss of the tRNA genes trnR-CCG, trnV-UAC, and trnR-UCU in fern plastomes was much more prevalent than previously thought. We also identified several codon indels in protein-coding genes within the core leptosporangiates, which may be identified as synapomorphies of specific families or higher ranks. This study provides an empirical case of integrating structural and sequence information of plastomes to resolve deep phylogeny of plants.

To determine the taxonomic identities and the systematic positions of some collections of Lindsaea sect. Synaphlebium (Lindsaeaceae) from Papua New Guinea, we conducted morphological comparisons and phylogenetic analyses on the whole section. A total of 22 morphological characters were selected and coded for each of all known taxa in L. sect. Synaphlebium, and were analyzed using maximum parsimony. The datasets containing either of or combined two plastid DNA sequences (trnL-trnF spacer and trnH-psbA spacer) of 37 taxa were analyzed using maximum parsimony, maximum likelihood, and Bayesian inference. Morphological comparisons revealed two new species which are formally published here as L. subobscura and L. novoguineensis. Lindsaea subobscura is similar to sympatric L. obscura and L. modesta but differs in the obviously reduced upper pinnules and other characters. Lindsaea novoguineensis is most similar to L. pacifica from Melanesia but differs in having rhomboid pinnules with truncate apices and concave soral receptacles. Molecular analyses resolved L. sect. Synaphlebium and allied species into five well-supported clades, namely L. rigida clade, L. obtusa clade, L. pulchella clade, L. multisora clade, and L. cultrata clade. The new species L. novoguineensis is included in L. obtusa clade; L. subobscura is in L. pulchella clade; whereas the majority of L. sect. Synaphlebium is clustered in L. cultrata clade. As the section Synaphlebium sensu Kramer is strongly suggested as polyphyletic, we propose the concept of a monophyletic L. sect. Synaphlebium in a broad sense that comprises five lineages. The morphological circumscription of L. sect. Synaphlebium sensu lato and the divergence in morphology, habit, and distribution between the five lineages are briefly discussed. Further molecular study is needed to test the systematic positions of 16 other species which are supposed to be within L. sect. Synaphlebium sensu lato but have not been included in this and previous molecular analyses.

The taxonomic subdivision of Cyatheaceae, a family containing over 600 species of scaly tree ferns, has troubled pteridologists for more than one century. Recent molecular analyses have revealed four monophyletic groups (Alsophila R. Br., Cyathea Sm., Gymnosphaera Blume, and Sphaeropteris Bernh.) within this family. However, one of the four groups, Gymnosphaera, was still submerged in Alsophila in a modern classification proposed by the Pteridophyte Phylogeny Group due to Gymnosphaera being phylogenetically underrepresented in previous studies. In this study, we add the sampling of Gymnosphaera from its main distribution area (southeastern Asia) and conduct phylogenetic analyses of datasets containing individual and combined five chloroplast DNA regions (rbcL, rbcL-accD, rbcL-atpB, trnG-trnR, and trnL-trnF) of 120 scaly tree ferns using three methods (maximum parsimony, maximum likelihood, and Bayesian inference). The result is congruent with previous studies, consistently resolving scaly tree ferns as four well-supported clades with Sphaeropteris sister to the other three, and shows a probability for the first time on the relationships between Alsophila, Cyathea, and Gymnosphaera, i.e., Alsophila is sister to Gymnosphaera and then together as sister to Cyathea. As supported to be distinct from Alsophila in molecular phylogeny, in morphology, and in sporogenetic mechanism, Gymnosphaera is reinstated here, with a minor emendation in circumscription, as a separate genus. To facilitate the application of species' names and future revision, we provide a checklist of 43 taxa now known in Gymnosphaera with information of nomenclatural types and general distributions; among them 25 are new combinations. [ABSTRACT FROM AUTHOR]