Insights into the evolutionary history and taxonomic status of Sinopteris (Pteridaceae).

As an endemic Chinese genus, Sinopteris C. Chr. & Ching was once considered an early diverged taxon of cheilanthoid ferns, and its taxonomic status has long been controversial. In this study, eight datasets spanning the complete chloroplast genomes and three nuclear genes were used to reconstruct the phylogeny of Sinopteris and its relatives. In addition, combining morphological analyses, divergence time estimation, and ancestral trait reconstruction, the origin and evolutionary history of Sinopteris were comprehensively discussed. Based on the complete chloroplast genome dataset, our analyses yielded a phylogram with all clades strongly supported (ML-BS = 100, BI-PP = 1.0), and the topology was almost identical to that based on the concatenated sequences of nrDNA, CRY2, and IBR3. Two species of Sinopteris were united and sister to Aleuritopteris niphobola (C. Chr.) Ching. They constituted a stable monophyletic group embedded in Aleuritopteris Fée. This was also consistent with the results of morphological analyses. Divergence time estimation indicated that the clade of Aleuritopteris and Sinopteris originated in the early Miocene (ca. 16.80 Ma) and experienced two rapid diversifications, which could coincide with environmental heterogeneity caused by the progressive uplift of the Himalayas and the intense uplift of the Hengduan Mountains. Sinopteris originated in the late Miocene (ca. 6.96 Ma), accompanied by the sharp intensifications of Asian Monsoon, and began to diversify at 2.34 Ma, following the intense uplift of the Hengduan Mountains. Ancestral character reconstruction showed that monangial sori and subsessile sporangia were clearly late derived states rather than early diverged states. Both the molecular phylogenetic and morphological analyses support the inclusion of Sinopteris in Aleuritopteris.

Characterization of the Dicranostigma leptopodum chloroplast genome and comparative analysis within subfamily Papaveroideae.

BACKGROUND: Dicranostigma leptopodum (Maxim.) Fedde is a perennial herb with bright yellow flowers, well known as "Hongmao Cao" for its medicinal properties, and is an excellent early spring flower used in urban greening. However, its molecular genomic information remains largely unknown. Here, we sequenced and analyzed the chloroplast genome of D. leptopodum to discover its genome structure, organization, and phylogenomic position within the subfamily Papaveroideae. RESULTS: The chloroplast genome size of D. leptopodum was 162,942 bp, and D. leptopodum exhibited a characteristic circular quadripartite structure, with a large single-copy (LSC) region (87,565 bp), a small single-copy (SSC) region (18,759 bp) and a pair of inverted repeat (IR) regions (28,309 bp). The D. leptopodum chloroplast genome encoded 113 genes, including 79 protein-coding genes, 30 tRNA genes, and four rRNA genes. The dynamics of the genome structures, genes, IR contraction and expansion, long repeats, and single sequence repeats exhibited similarities, with slight differences observed among the eight Papaveroideae species. In addition, seven interspace regions and three coding genes displayed highly variable divergence, signifying their potential to serve as molecular markers for phylogenetic and species identification studies. Molecular evolution analyses indicated that most of the genes were undergoing purifying selection. Phylogenetic analyses revealed that D. leptopodum formed a clade with the tribe Chelidonieae. CONCLUSIONS: Our study provides detailed information on the D. leptopodum chloroplast genome, expanding the available genomic resources that may be used for future evolution and genetic diversity studies.

The complete chloroplast genome sequence of Ranunculus pekinensis (L. Liou) Luferov (Ranunculaceae), a species endemic to China.

Ranunculus pekinensis (L. Liou) Luferov 1997, a perennial aquatic herb, is endemic to Beijing, China and has high water quality requirements. Because its habitat is under great threat and its population is declining, it is now listed as a national protected plant in China. To provide genomic resources for future research of this endangered species, the complete chloroplast genome sequence of R. pekinensis was assembled and annotated for the first time. The complete chloroplast genome sequence was 156,139 bp in length, containing a large single copy region (LSC) of 85,430 bp and a small single copy region (SSC) of 19,970 bp, which were separated by a pair of 25,367 bp inverted repeat regions (IRs). The complete chloroplast sequence contained 112 unique genes, including 30 tRNA, 4 rRNA, and 78 protein-coding genes. The overall guanine-cytosine (GC) content of the chloroplast genome was 37.8%, and the GC contents of the LSC, SSC, and IR regions were 36.0%, 31.3%, and 43.5%, respectively. Phylogenetic analysis with the reported chloroplast sequences showed that R. pekinensis was closely related to R. bungei Steud. 1841, both of which belonged to Ranunculus Sect. Batrachium DC. 1817. These data will provide essential resources regarding the evolution and conservation of R. pekinensis.

The complete chloroplast genome of a distinctive fern, Coniogramme intermedia Hieron. (Pteridaceae).

Coniogramme intermedia Hieron. is a morphologically distinctive species in the genus. It is identified by lanceolate pinnules with serrated margins, free veins, hydathodes extending into teeth, and laminae abaxially hairy. It is mainly distributed in the tropical and subtropical regions of Asia. Herein, we report the first complete chloroplast genome sequence of C. intermedia. Also, it is the opening one of the genus Coniogramme Fée. The chloroplast genome sequence is 153,561 bp in length. The genome has a typical quadripartite structure, including a large single-copy (LSC) region of 82,817 bp, a small single-copy (SSC) region of 21,236 bp, and two inverted repeat (IR) regions of 24,754bp each. The total GC content is 45.0%. The complete plastome sequence contains 114 genes, including, 81 protein-coding, 29 tRNA, and four rRNA genes. The phylogenetic analysis of Pteridaceae based on the complete chloroplast genomes was also presented in this study.

Two new records of the fern genus Coniogramme (Pteridaceae) from Vietnam.

Two new records of the fern genus Coniogramme Fée from Vietnam, C.japonica and C.procera, are presented. In addition, a key to recognising the species of Coniogramme in Vietnam is given in this paper.

Identifying appropriate protected areas for endangered fern species under climate change.

The management of protected areas (PAs) is widely used in the conservation of endangered plant species under climate change. However, studies that have identified appropriate PAs for endangered fern species are rare. To address this gap, we must develop a workflow to plan appropriate PAs for endangered fern species that will be further impacted by climate change. Here, we used endangered fern species in China as a case study, and we applied conservation planning software coupled with endangered fern species distribution data and distribution modeling to plan conservation areas with high priority protection needs under climate change. We identified appropriate PAs for endangered fern species under climate change based on the IUCN protected area categories (from Ia to VI) and planned additional PAs for endangered fern species. The high priority regions for protecting the endangered fern species were distributed throughout southern China. With decreasing temperature seasonality, the priority ranking of all endangered fern species is projected to increase in existing PAs. Accordingly, we need to establish conservation areas with low climate vulnerability in existing PAs and expand the conservation areas for endangered fern species in the high priority conservation regions.