Oreocharis wenshanensis W.H.Chen & Y.M.Shui, 2019

Chen, Wen-Hong, Zhang, Ya-Mei, He, De-Ming, Li, Yong-Liang & Shui, Yu-Min, 2019, Four new species of Oreocharis (Gesneriaceae) in Yunnan province, China, PhytoKeys 157, pp. 83-99 : 83

Oreocharis wenshanensis W.H.Chen & Y.M.Shui sp. nov. Fig. 7

Diagnosis.

The new species is most similar in leaves to Oreocharis concava (Craib) Mich. Möller & A.Weber, but differs in broadly ovate leaf blade (vs. oblong-ovate), remotely pubescent adaxial leaf surface (vs. villous), calyx margin crenate (vs. irregularly dentate), the shorter corolla (1.5-1.6 cm long vs. 2.2-2.8 cm), adaxial corolla lip bilobed (vs. emarginate to undivided) and disc subentire (vs. 5-lobed).

Type.

CHINA. Yunnan Province: Wenshan county, Bozu Mt., 23°21'1.41"N, 103°55'6.20"E, in dense forests, elev. 2,700 m, 27 July 1993, in flower, Shui Y.M. 3126 (holotype, KUN!; isotype, PE!).

Description.

Herb perennial, stemless, rhizomatous. Leaves many, basal; petiole 5-9 cm, densely pubescent; leaf blade broadly ovate, chartaceous, 5.0-9.0 × 3.7-7.0 cm, adaxially sparsely pubescent and abaxially along veins, base cordate, apex acuminate, margin biserrate, lateral veins 4-5 on each side of midrib, indistinct adaxially and distinct abaxially. Inflorescences axillary, peduncle 6-10 cm, densely pubescent; bracts narrowly oblong, ca. 0.9 × 0.2 cm, adaxially glabrous, abaxially sparsely pubescent, apex acuminate, margin serrate above middle and entire below middle. Inflorescences axillary, densely cymose. Peduncles 5-7 cm, pubescent; Pedicels 2.0-2.8 cm, pubescent. Calyx 6-7 mm, 5-sect from 2/3; segments equal, triangular, ca. 3 × 2 mm, adaxially glabrous, abaxially pubescent, margin serratulate. Corolla yellow, 1.5-1.6 cm long, outside pubescent and inside glabrous; tube cylindrical, gradually slightly widening from middle of tube, 0.7-1.0 cm long, ca. 0.3 cm in diam., throat not constricted; limb 2-lipped; adaxial lip smaller, ca. 3 mm long, 2-lobed, lobes oblong, apex obtuse, 1-1.5 × ca. 1.5 mm; abaxial lip larger, 4-5 mm long, 3-lobed, lobes oblong, apex acute, central lobe 4-5 × ca. 3 mm, lateral lobes ca. 3 × 3 mm. Stamens 4, coherent in 2 pairs, included, adaxial stamens ca. 2 mm, adnate to corolla tube ca. 3 mm from base, abaxial stamens ca. 4 mm, adnate to corolla tube ca. 3 mm from base; filaments tender, glabrous; anthers basifixed, oblong, 2-loculed, dehiscing longitudinally; staminode 1, 1-2 mm, adnate to corolla tube 2-3 mm from base. Disc ring-like, 1-2 mm, subentire. Pistil 2.5-6 mm, glabrous; ovary oblong, glabrous, 1-4 mm, 1-loculed; style glabrous, 1.5-2 mm; stigma 1, top retuse. Capsule straight, oblong, 1.3-1.8 cm, existing style ca. 0.2 cm. Seeds not seen.

Distribution, habitat and phenology.

The new species only grows in the montane forest in Wenshan county, Yunnan Province of China. Flowering is July-September; and fruiting is October-January the following year.

Etymology.

The species is named after the type locality of the new species.

Conservation status.

Currently, the new species has been observed only from the type locality. The more than two years observation revealed that there are ca. 50 mature individuals and ca. 300 m2 (10 m × 30 m) area nearby the summit in the core area of the nature reserve, similarly to the above species ( O. lacerata ). According to the IUCN Red List Categories and Criteria, the new species is hereby assessed as "Critically Endangered (CR)" (D1+D2). ( IUCN 2012)

Additional specimens examined (paratypes).

CHINA. Yunnan Province: Wenshan county, Laojun Mt., on rocks in forests, 23°21'1.41"N, 103°55'6.20"E, 31 August 2012, in flower, Shui Y.M., He D.M. et al. B2012-099 (KUN); the same locality, on rocks in bamboo, 23°21'1.45"N, 103°55'6.24"E, 24 June 2013, Shui Y.M. & Xiao B. B2013-100C (KUN).

Note.

Oreocharis wenshanensis was collected first in 1993 by Y. M. Shui in Wenshan county, SE Yunnan, China (Fig. 2G-K ). In 2005, the new species was wrongly identified as Oreocharis aurea Dunn var. cordato-ovata (C.Y. Wu ex H.W. Li) K.Y. Pan, A.L. Weitzman & L.E. Skog, based on the photo in Li and Wang (2005) possibly because of their similar locality in SE Yunnan. However, the latter species endemically grows in the limestone forests in Xichou county, the neighbouring county of Wenshan county, a very different habitat from Oreocharis wenshanensis . Furthermore, the new species we proposed can be easily distinguished from Oreocharis aurea Dunn var. cordato-ovata by its broadly ovate blade, smaller corolla without contracted throat and bilobed adaxial corolla lips ( Li and Wang 2005). In fact, due to its 2700 m elevation, it is morphologically more similar to O. concava from NW Yunnan with 3100-3400 m elevation (Fig. 7 , Table 4 ). After more than 20 years of observation, with the support of local staff of the Nature Reserve, we made a long-term observation from 1993 to 2018 and confirmed its taxonomic novelty.

Figures

Figure 2. Oreocharis eriocarpa W. H. Chen & Y. M. Shui, sp. nov. (A-F) A habit B leaf adaxial surface C leaf abaxial surface D bracts E ovary and disc F dense pubescent ovary and disc; O. wenshanensis (G-K) G habitat H plant I leaf adaxial surface J leaf abaxial surface K flower. Photography by He De-Ming (A-E, K), Zhang Ting (E), Chen Li (F), Shui Yu-Min (G, I, J).

Figure 7. Oreocharis wenshanensis W. H. Chen & Y. M. Shui, sp. nov. A plant B opened corolla showing stamens and staminode C pistil showing ovary, disc and stigma D calyx. (Drawn by Ling Wang from holotype).