Oreocharis wumengensis, a new species of Gesneriaceae from northeastern Yunnan, China

Abstract A new species of Gesneriaceae, Oreocharis wumengensis Lei Cai & Z.L.Dao from Wumeng Mountain area, Yanjin County, Yunnan Province, China, is described. The new species is morphologically similar to O. panzhouensis Lei Cai, Y.Guo & F.Wen in the shape of corolla, number of stigma and stamens, but it can be easily distinguished from this species by the leaf shape and indumentum characters of leaf blade, calyx and stamens. Detailed descriptions with photographs of the plant and holotype, and comparisons with morphologically similar species, are also provided.


Introduction
Many genera and species in the family Gesneriaceae have been redefined in the past two decades based on new evidence following the development of molecular phylogenetics (Möller et al. 2011(Möller et al. , 2016Weber et al., 2011aWeber et al., , 2011b. Oreocharis Bentham was redefined in 2011 (Möller et al. 2011), and the vast majority associated species of the other 10 genera were merged into the enlarged genera , including some new taxa described in recent years (Cai et al. 2015(Cai et al. , 2017(Cai et al. , 2019Chen et al. 2017Chen et al. , 2018Do et al. 2017;Guo et al. 2018;Han et al. 2017;Möller 2015;Möller et al. 2018;Wei et al. 2016;Yang et al. 2018), Oreocharis s.l. now comprises ca. 120 species, mainly with southern and southwestern Chinese distribution, but with a few species extending into Vietnam, Myanmar, India, Bhutan, Japan and Thailand (Cai et al. 2017(Cai et al. , 2019Chen 2016;Chen et al. 2017Chen et al. , 2018Do et al. 2017;Guo and Wang 2014;Li and Wang 2004;Möller et al. 2018;Wang et al. 1990Wang et al. , 1998Xu et al. 2017).
In April 2017, during field investigations in the Wumeng Mountain area (Yanjin County, northeastern Yunnan), an unknown species of Gesneriaceae without flowers was collected and then planted in Kunming Botanical Garden (KBG). In July 2018, we firstly observed flowering plants which were cultivated in KBG, also based on the floral characteristics; we confirmed that it is a member of Oreocharis s.l. Following a careful review of the relevant herbarium specimens and taxonomic publications of Oreocharis from Yunnan and the adjacent regions, we concluded that this species is new to science. Oreocharis wumengensis Lei Cai & Z.L.Dao is described for the first time below, and its morphological characters are compared with those of closely related species.

Oreocharis wumengensis
Phenology. Flowering from July to August; fruiting unknown. Etymology. The specific epithet 'wumengensis' referring to the type locality where the new species was found, is located in the famous Wumeng Mountain area.
Distribution and ecology. Oreocharis wumengensis is currently known only from one population of ca. 50 individuals at the type locality. The species could be endangered, but more data is needed to evaluate this reliably. The species was observed growing on moist rocks with other plants under forest cover in karst regions in Yanjin County, Yunnan.
Taxonomic affinities. Oreocharis wumengensis is morphologically unique with sigmoid corolla within Oreocharis s.l., however there are certain similarities with other species in this genus. O. wumengensis is similar to O. panzhouensis in the shape of corolla, however, it is obviously different from the latter species. The comparison of morphologically characters on related species are provided in Table 1.