Fig 1.
Broad-leaved evergreen forest and expanding coffee plantation in Langbiang Plateau.
As in much of the tropical countries, the biodiverse montane forests of the Langbiang Plateau are being cleared for agriculture such as coffee plantation, threatening the native flora and fauna and the ecosystem functions (photo: C.-W. Chen).
Fig 2.
Distribution of Langbiangia and Primulina.
The map was generated using QGIS 3.24.1 [60]. The basemap of karst aquifers was downloaded from WHYMAP [61], which can be freely used and copied for educational and other non-commercial purposes. The distributions were mapped based on occurrence records retrieved from Global Biodiversity Facility [62]. The distribution of Langbiangia poilanei was plotted based on information taken from the holotype. This work is licensed under a CC BY 4.0 license.
Fig 3.
(A) Habit. (B) Corolla, longitudinal dissection with stamens. (C) Disc, ovary and style. Photos by Hong Truong Luu and Minh Tri Dang.
Fig 4.
Phyllotaxy of Langbiangia and Primulina.
(A) Langbiangia annamensis, photo by Maxim S. Nuraliev / CC BY-NC 4.0 (https://www.inaturalist.org/observations/38536524) (B) The acaulescent stem of Langbiangia scutellifolia. (C) Primulina minutimaculata. (D) Primulina dryas. (E) Primulina lungzhouensis. (F) Primulina minor. B–E by C.-L. Hsieh, and F by K.-F. Chung.
Table 1.
Sampling information and GenBank accession numbers of newly sequenced individuals.
All voucher specimens were deposited in the Herbarium of Southern Institute of Ecology (SGN).
Fig 5.
Simplified Bayesian inference tree of Didymocarpoideae based on combined trnL-F and ITS sequences.
Numbers at the node indicate Bayesian posterior probability (≥ 0.5), with ML bootstrap value (≥ 50%) shown after slash (/). All genera except for Primulina, Deinostigma and Langbiangia gen. nov. are collapsed into triangles, with gray triangles denoting genera/clades that are fully supported in both Bayesian and ML analyses. The infrafamilial classification of Weber et al. 2013 [77] and Weber et al. 2020 [63] is followed. This tree is simplified from the S3 Fig. ML bootstrap values are retrieved from S5 Fig.