Cycas multipinnata C.J. Chen & S.Y. Yang is a cycad endemic to the Red River drainage region that occurs under evergreen forest on steep limestone slopes in Southwest China and northern Vietnam. It is listed as endangered due to habitat loss and over-collecting for the ornamental plant trade, and only several populations remain. In this study, we assess the genetic variation, population structure, and phylogeography of C. multipinnata populations to help develop strategies for the conservation of the species. 60 individuals from six populations were used for chloroplast DNA (cpDNA) sequencing and 100 individuals from five populations were genotyped using 17 nuclear microsatellites. High genetic differentiation among populations was detected, suggesting that pollen or seed dispersal was restricted within populations. Two main genetic clusters were observed in both the cpDNA and microsatellite loci, corresponding to Yunnan China and northern Vietnam. These clusters indicated low levels of gene flow between the regions since their divergence in the late Pleistocene, which was inferred from both Bayesian and coalescent analysis. In addition, the result of a Bayesian skyline plot based on cpDNA portrayed a long history of constant population size followed by a decline in the last 50,000 years of C. multipinnata that was perhaps affected by the Quaternary glaciations, a finding that was also supported by the Garza-Williamson index calculated from the microsatellite data. The genetic consequences produced by climatic oscillations and anthropogenic disturbances are considered key pressures on C. multipinnata. To establish a conservation management plan, each population of C. multipinnata should be recognized as a Management Unit (MU). In situ and ex situ actions, such as controlling overexploitation and creating a germplasm bank with high genetic diversity, should be urgently implemented to preserve this species.

Two new species of Oreocharis Benth. from Fan Si Pan, the highest mountain in Vietnam (Sa Pa) are described and illustrated. Oreocharis grandiflora W.H.Chen, Q.H.Nguyen & Y.M.Shui, is similar to O. flavida Merr. from Hainan province, China, but differs mainly by its larger and infundibuliform corolla, stamens adnate to the base of the corolla tube and stamens coherent in two pairs. The second, Oreocharis longituba W.H.Chen, Q.H.Nguyen & Y.M.Shui, is similar to O. hirsuta Barnett, endemic to northern Thailand, but mainly differs in its pubescence, coherent stamens and glabrous filaments.

We describe and illustrate four new species, Peliosanthes choriandra, P. tatianae and Tupistra orlovii from central to northern Laos, and Rohdea filosa from northern Vietnam. These are all very local in distribution and endemic to the respective countries. We also report new localities and their ecological conditions for five other species of Peliosanthes (P. argenteostriata, P. hirsuta, P. irinae, P. micrantha and P. nivea) recently described from Laos and/or Vietnam. Furthermore, Peliosanthes nivea is recorded as new to the flora of Laos.

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from the Xuan Nha nature reserve, Van Ho district, Son La province, in northwestern Vietnam are described. They are compared to their most similar species and diagnostic characteristics are provided.

This paper continues the publication of newly obtained results from a continuing taxonomic investigation of the genus Aspidistra in mainland southeast Asia. It includes descriptions and illustrations of seven taxa discovered in China and Vietnam, A. deflexa Aver., Tillich & V.T. Pham, A. heterocarpa Aver., Tillich & V. T. Pham var. heterocarpa, A. heterocarpa Aver., Tillich & V. T. Pham var. echinata Aver., Tillich & T.A. Le, A. nigra Aver., Tillich & K. S. Nguyen, A. sessiliflora Aver. & Tillich, A. sinuata Aver. & Tillich and A. tonkinensis (Gagnep.) F. T. Wang & K. Y. Lang var. compacta Aver. & Tillich. Specific taxonomic status is proposed for A. vietnamensis (Aver. & Tillich) Aver & Tillich. described at first as a variety of A. elatior Blume. The name A. connata Tillich is accepted as a synonym of A. subrotata Y. Wan & C. C. Huang. One species, A. hainanensis W. Y. Chun & F. C. How is reported as new for the flora of Vietnam, and another one, A. semiaperta Aver. & Tillich as new for the flora of Laos. New or updated data on ecology, phenology, tentative relationships, distribution and conservation status are reported for all mentioned taxa.

The genus Aspidistra Ker-Gawler (1822 plate 628), overlooked for decades, is recently remarkably fast growing. During the past decade, about 90 species new to science were discovered and described, mainly from southern China, Vietnam, and Laos. With its diversity in flower morphology Aspidistra is among the most spectacular genera of Monocotyledons. Vietnam turned out to be especially rich in Aspidistra species (Tillich 2014), and at, least 30 additional species were discovered and described recently in this country (Averyanov & Tillich 2014, 2015, 2016, 2017, Leong-Skornickova et al. 2014, Vislobokov et al. 2014a, b, 2016a, b, 2017, Vislobokov 2015, 2016, Olivier 2015, Averyanov et al. 2016, 2017, 2018a, b, Nguyen et al. 2017, Tillich et al. 2017, Tillich & Averyanov 2018). Meanwhile, the diversity of the genus in Vietnam remains insufficiently inventoried. Below we describe three more new species from central Vietnam.

Since 2016, KIB (Kunming Institute of Botany) and CPC (Centre for Plant Conservation of Vietnam) have conducted several surveys in the transboundary karst regions in Northern Vietnam and Southern China and seven new species in the genus Begonia Linn. (Begoniaceae) are firstly described. Amongst them, two species, Begonia albopunctata Y.M. Shui, W.H. Chen & H.Q. Nguyen and B. erectocarpa H.Q. Nguyen, Y.M. Shui & W.H. Chen, respectively belong to section Sphenanthera with berry fruits and section Leprosae with clavate berry fruits; four species, B. gulongshanensis Y.M. Shui & W. H. Chen, B. minissima H.Q. Nguyen, Y.M. Shui & W.H. Chen, B. mollissima Y.M. Shui, H.Q. Nguyen & W.H. Chen, B. rhytidophylla Y.M. Shui & W.H. Chen, belong to section Coelocentrum with parietal placentation; one species, Begonia bambusetorum H.Q. Nguyen, Y.M. Shui & W.H. Chen, belongs to section Diploclinium with 3-loculed ovary and capsules. The diagnostic characters of these species are described and illustrated in the text and photographs.