The disparate distribution of apomixis between the major plant lineages is arguably one of the most paradoxical phenomena in plant evolution. Ferns are particularly interesting for addressing this issue because apomixis is more frequent than in any other group of plants. Here, we use a phylogenetic framework to explore some aspects of the evolution of apomixis in ferns and in particular in the polystichoid ferns. Our findings indicate that apomixis evolved several times independently in three different clades of polystichoid ferns. A lineage-wide perspective across ferns indicates a correlation between apomixis and the species richness of lineages; however BiSSE tests did not recover evidence for a correlation of apomixis and diversification rates. Instead, evidence was recovered supporting an association between the establishment of apomixis and reticulate evolution, especially in the establishment of triploid hybrids. Diversification time estimates supported the hypothesis of short living apomictic lineages and indicated a link between the establishment of apomixis and the strengthening of the monsoons caused by the lifting of the Qinghai-Tibetan plateau. In general our results supported the hypothesis for the rare establishment of apomictic lineages, high extinction risks, and low speciation rates.

Premise of the study:Here we report the complete chloroplast genome of the important medicinal species Huperzia serrata (Lycopodiaceae) and compare it to the chloroplast genome of the congeneric species H. lucidula.Methods and Results:The whole chloroplast genome of H. serrata was sequenced using an Illumina platform and assembled with Geneious version R9.0.5. The genome size of H. serrata was 154,176 bp, with 36.3% GC content. The complete chloroplast genome contained 120 unique genes, including 86 coding genes, four rRNA genes, and 30 tRNA genes. Comparison with the chloroplast genome of H. lucidula revealed three highly variable regions (rps16-chlB, ycf12-trnR, and ycf1) between these two species and 252 mutation events including 27 insertion/deletion polymorphisms and 225 single-nucleotide polymorphisms (SNPs). Ninety-two SNPs were identified in the gene-coding regions. In addition, 18 microsatellite sites were found, which can potentially be used in phylogeographic studies.Conclusions:The complete chloroplast genome of H. serrata is reported here, and will be a valuable genome resource for further phylogenetic, evolutionary, and medical studies of medicinal plants in the genus Huperzia.

Oreocharis duyunensis Z.Y. Li, X.G. Xiang et Z.Y. Guo (Gesneriaceae), endemic to Guizhou, China, is described as a new species. The new species is easily distinguished from other Oreocharis species by having a white, stellate ring‐like disc. Morphologically, the species is similar to Oreocharis chienii (Chun) Mich. Möller & A. Weber but differs by its densely white pilose leaves, mixed brown‐pilose, pubescent and glandular‐pubescent peduncle and pedicle, white stellate ring‐like disc, and linear‐lanceolate capsule. Based on phylogenetic reconstruction and interspecific genetic distances of nuclear ITS and chloroplast trnL‐F regions, O. duyunensis is a new species with uncertain phylogenetic position.

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Hemiboeaalbiflora X.G.Xiang, Z.Y.Guo & Z.W.Wu, sp. nov., a new species of Gesneriaceae from Guizhou, China, is described and illustrated. This species was previously listed informally as a variety of H.gamosepala, but it differs significantly from H.gamosepala by its 5-parted calyx from the base, longer peduncle, white corolla and longer pistil. Based on recent extensive observations, this new species is similar to H.cavalerieivar.paucinervis and H.subcapitata but differs from them by its longer petiole, larger involucre, white corolla and longer staminal filaments. The conservation status of this species is considered to be “Vulnerable” (VU) according to the IUCN Red List Categories and Criteria.

Based on microwave-assisted extraction (MAE) and headspace solid-phase microextraction (HS-SPME) followed by gas chromatography mass spectrometry (GC-MS) was developed for the fast determination of volatile chemical compositions of Polygala furcata Royle, the experimental parameters of the MAE-HS-SPME were optimized by orthogonal experimental design. The results indicated that the optimum condition of the determination of the volatile compounds in P. furcata Royle. was achieved with the experimental parameters including microwave power of 400 W and irradiation time of 4 min, sample size 2.0 g. Under the optimal conditions, for the Wrst time, 52 volatile compounds were separated and identiWed from the fresh plants of P. furcata Royle. The highest content component of the 52 compounds was 2-hydroxybenzoic acid methyl ester (21.65%). The relative standard deviation values <7% showed that the method of MAE-HS-SPME followed by GC-MS has good precision. The experimental results demonstrated that it is a simple, time-saving and solvent-free method, and it is a potential analytic tool for the determination of the volatile compounds of the vegetations materials and other materials.

The taxonomic problem of cryptic species has long been recognized. Hemiboea subcapitata C. B. Clarke is a widespread and morphologically diverse species including two varieties, H. subcapitata var. subcapitata C. B. Clarke and H. subcapitata var. guangdongensis (Z. Y. Li) Z. Y. Li. However, genetic distance and molecular phylogenetic analyses based on nuclear ITS and four plastid DNA sequences (atpB‐rbcL, matK, rbcL, rpS16 intron) revealed that H. subcapitata var. guangdongensis is sister to H. subacaulis, and separated from H. subcapitata var. subcapitata, suggesting that it should be raised to the rank of an independent species as H. guangdongensis (Z. Y. Li) X. Q. Li & X. G. Xiang, comb. & stat. nov. Morphologically, the new species can be distinguished from H. subacaulis by its calyx 5‐sect from base, segments narrowly oblong‐lanceolate (versus calyx 5‐sect from base or 2‐lipped and adaxial lip 2‐lobed from below middle, segments ovate), peduncle glabrous (versus pubescent), and vermiform sclereids dispersed in leaf mesophyll (versus without sclereids).

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