Hou-Hua Fu

Aristolochia minjiangyuanensis, a new species of Aristolochia subgen. Siphisia from Jianning County, Fujian Province, China, is described and illustrated. Morphologically, it differs in having usually narrower, narrowly ovate-cordate leaves with a long-acuminate or acute apex, a subobovate perianth limb with the lower lobe significantly longer than the upper two lobes and an unspotted inner surface, a smaller throat, and an indumentum predominantly composed of grayish-white velvety hairs. Phylogenetic analyses, based on the nuclear ribosomal ITS region (5.8S + ITS2) and the plastid trnK region, support the placement of A. minjiangyuanensis within the A. kaempferi group, while the trnK analysis further strongly supports a sister relationship between the new species and A. vestita. The new species can be distinguished from A. vestita by its subobovate perianth limb with a revolute apex and an inner surface without spots or stripes, subcircular throat, and predominantly grayish-white velvety indumentum. It differs from A. kaempferi mainly in the morphology and markings of the perianth limb and in having a cylindrical, velvety capsule.

A new species, Castanopsis pachycupula (Fagaceae), is described and illustrated from Bidoup Nui Ba National Park, Vietnam. Morphologically, C. pachycupula closely resembles C. dongchoensis, but it can be distinguished by its leaf and nut morphology, as well as by the cupule features. Phylogenetic analyses based on complete chloroplast genome sequences of genus Castanopsis strongly support a close relationship between the new species and C. dongchoensis. Both taxa morphological characteristics and molecular evidence provide a robust support suggesting a distinct species of C. pachycupula. In addition, the complete plastid genome of this new species is reported.

Selaginella magna (Selaginellaceae), a new species in S. subg. Stachygynandrum from Guangxi, Fujian and Hunan, China, is here described and illustrated. It is the largest erect Selaginella species in China, characterized by acropetally shortening branches acropetally. Selaginella magna is most similar to S. willdenowii , but can be differentiated by its erect main stem, rhizophores restricted to rhizomes and stolons, and the absence of auricles at the base of both ventral and axillary leaves. Its triangular frond-like leafy stem with an acuminate apex confers a high degree of distinguishability in its natural habitat.

We described and illustrated a new species, Bulbophyllum meihuashanense (Epidendroideae, Orchidaceae), from southern Fujian, China. The new species is morphologically similar to B. yongtaiense, but differs by its shorter blade, flower scape (umbel 2–3 flowered vs. umbel 3–5 flowered), dorsal sepals (with 3-veined vs. 5-veined), petals (gradually acute apex vs. apex obtuse), and lip (ligulate, adaxially shallowly grooved vs. ovate, adaxially deeply grooved). Molecular analysis based on the nuclear (ITS and Xdh) and plastid (matK and psbA-trnH) sequences confirms its status as a new species.

Endophytic fungi enhance plant growth and stress resilience, yet their molecular roles in the roots of the endangered tree Phoebe bournei remain unclear. A comparative RNA-seq analysis was performed on root transcriptomes from wild, endophyte-colonized adult trees (OT) and axenically grown seedlings (ST). Unmapped reads were analyzed against the NCBI nucleotide (NT) database using BLASTN (v2.17.0), revealing Rhizophagus irregularis as the predominant endophytic fungus. Differential expression analysis identified 5891 DEGs, which were significantly enriched in pathways related to plant–pathogen interactions, phenylpropanoid biosynthesis, plant hormone signal transduction, and MAPK signaling. Key upregulated genes included PbMPK3, PbCML42, PbCML41.2, and PbGSTU28, suggesting enhanced ROS scavenging, calcium signaling, and defense activation. RT-qPCR validation confirmed the transcriptomic trends for selected genes. Our findings reveal that root endophytic fungi modulate a coordinated network involving immune priming, phytohormone regulation, and redox homeostasis, thereby supporting root development and enhancing resistance to biotic and abiotic stresses in P. bournei. This study provides foundational molecular insights into beneficial plant–endophyte interactions and identifies candidate genes that are valuable for the conservation and breeding of this threatened species.

A new species, Leptochilus dolichophyllus (Polypodiaceae), from central‐northern Fujian, southeastern China, is described and illustrated. It is morphologically similar to Leptochilus leveillei , but differs by its hemiepiphytic habit and longer frond. Molecular phylogenetic analysis based on three plastid regions ( rbcL , rps4 + rps4 ‐ trnS , and trnL + trnL‐trnF ) demonstrates that the new species represents a distinct and well‐supported clade. Both morphological and molecular data provide compelling evidence for the recognition of L. dolichophyllus as a new species. Furthermore, the complete plastid genome of this new species is reported.

The MADS-box transcription factor gene family is essential for the differentiation and development of floral organs. Genome-wide and transcriptome data from Phoebe bournei provide the foundation for studying its floral development. In this study, phylogenetic relationships, protein characteristics, conserved domains, gene structures, and cis-acting elements in promoter regions of P. bournei MADS-box genes were systematically analyzed through bioinformatics methodologies. A total of 69 PbMADS genes were identified and classified into 15 subfamilies based on their phylogenetic relationships. The potential functions of these genes were inferred based on transcriptomic data and GO classification. In addition, we selected genes from the ABCDE model to analyze protein interactions and performed RT-qPCR to analyze their expression in each floral organ whorl (outer tepals, inner tepals, stamens, and carpel). Based on these analyses, we rationally constructed a model for the floral organ development in P. bournei. This study, thus, provides a theoretical reference for germplasm innovation in P. bournei and offers insights into the floral development in other Lauraceae species.

The Tripterospermum, comprising 34 species, is a genus of Gentianaceae. Members of Tripterospermum are mostly perennial, entwined herbs with high medicinal value and rich in iridoids, xanthones, flavonoids, and triterpenes. However, our inadequate understanding of the differences in the plastid genome sequences of Tripterospermum species has severely hindered the study of their evolution and phylogeny. Therefore, we first analyzed the 86 Gentianae plastid genomes to explore the phylogenetic relationships within the Gentianae subfamily where Tripterospermum is located. Then, we analyzed six plastid genomes of Tripterospermum, including two newly sequenced plastid genomes and four previously published plastid genomes, to explore the plastid genomes’ evolution and phylogenetic relationships in the genus Tripterospermum. The Tripterospermum plastomes have a quadripartite structure and are between 150,929 and 151,350 bp in size. The plastomes of Tripterospermum encoding 134 genes were detected, including 86 protein-coding genes (CDS), 37 transfer RNA (tRNA) genes, eight ribosomal RNA (rRNA) genes, and three pseudogenes (infA, rps19, and ycf1). The result of the comparison shows that the Tripterospermum plastomes are very conserved, with the total plastome GC content ranging from 37.70% to 37.79%. In repeat sequence analysis, the number of single nucleotide repeats (A/T) varies among the six Tripterospermum species, and the identified main long repeat types are forward and palindromic repeats. The degree of conservation is higher at the SC/IR boundary. The regions with the highest divergence in the CDS and the intergenic region (IGS) are psaI and rrn4.5-rrn5, respectively. The average pi of the CDS and the IGS are only 0.071% and 0.232%, respectively, indicating that the Tripterospermum plastomes are highly conserved. Phylogenetic analysis indicated that Gentianinae is divided into two clades, with Tripterospermum as a sister to Sinogeniana. Phylogenetic trees based on CDS and CDS + IGS combined matrices have strong support in Tripterospermum. These findings contribute to the elucidation of the plastid genome evolution of Tripterospermum and provide a foundation for further exploration and resource utilization within this genus.

We have described and illustrated a new species, Luisia brachyota (Epidendroideae, Orchidaceae), from south Yunnan, China. Morphological comparisons indicated the new species is similar to L. filiformis and L. cordata, but differs from L. brachyota inflorescences 3-or 5-flowered, lip shorter than petals, hypochile thickly fleshy, epichile cordate adaxially with 7 or 9 papillate longitudinal ridges. Molecular analysis based on the nuclear ribosomal ITS and plastid sequences (matK, rbcL, and trnL-trnF) shows that it is a new species.