Oreocharis synergia W.H.Chen, Y.M.Shui & Mich.Möller, 2015

Chen, Wen-Hong, Möller, Michael, Chen, Run-Zheng, Rui, Rong-Ju & Shui, Yu-Min, 2015, Oreocharis synergia, a new species of Gesneriaceae from Northwestern Yunnan, China, Phytotaxa 233 (1), pp. 90-93 : 90-93

Oreocharis synergia W.H.Chen, Y.M.Shui & Mich.Möller , sp. nov. ( Fig. 1 )

The new species is most similar in leaf and floral characteristics to O. bodinieri H. Léveillé (1915: 40) , but differs from this species by its larger oblong or elliptic leaf blade, smaller lanceolate or triangular calyx lobes, light yellow corolla with rededged lobes, densely villous exterior corolla surface, glabrous upper half of the filament and glabrous connective.

Type:— CHINA. Yunnan Province: Yongsheng County, Renhe Township, Shanyila , on mountain slopes, 26°26 ′ N, 100°56 ′ E, elevation 2194 m, 27 Sept. 2014, in flower, Y. M. Shui et al. B2014-299 (holotype, KUN!; isotype, E!) .

Herbs perennial, stemless. Leaves in basal rosette. Petiole 5–10 cm long, long brown strigose; leaf blade oblong or elliptic, 12–20 × 5–10 cm, base cordate, slightly oblique, adaxially green and densely white hispid and long brown strigose, abaxially greenish and densely white pubescent, long brown strigose along veins, margin widely crenate; lateral veins 7–9 pairs on each side of midrib. Inflorescences axillary, few, 4–13 flowered. Peduncles 7–20 cm long, long brown strigose; bracts 2, linear, ca. 1 × 0.25 cm. Calyx 5-sect to middle, calyx tube 1.6–4 mm long, lobes lanceolate or triangular 2–5 mm long, 2–3 mm wide at base, both surfaces long brown strigose. Corolla light yellow with red lobe margins, slightly bilabiate, 1.8–2.4 cm long, outside white or brown villous, inside glabrous; tube cylindric, 1.8–2 cm long, 5–6 mm in diam.; adaxial lip 2-lobed, lobe semielliptic, ca. 4 × 2.3 mm; abaxial lip 3-lobed, lobes nearly equal, semielliptic, ca. 4.5 mm in diam. Stamens 4, free, included, almost equal; filaments white, white pubescent below the middle, 1.6–1.7 cm long; anthers oblong, basifixed, dehiscing longitudinally, connective glabrous; staminode absent or 1, linear, ca. 1 cm long, adnate to adaxial side of corolla tube ca. 7 mm from base. Pistil included at beginning of flowering, then distinctly exserted 3–4 mm, 2–2.6 cm long, glabrous; ovary ridged, glabrous, 1.3–1.5 cm long, 2-loculed; stigma 1, disc-shaped; disc 4–5-lobed to near middle, yellow, ca. 3 mm high, lobes lanceolate or linear. Capsule straight, narrowly oblong, 2–4 cm long. Seeds oblong ca. 1 mm long, not appendaged, numerous.

Distribution and habitat:— China. Oreocharis synergia is only found in three populations at the type locality (26°26 ′ N, 100°56 ′ E) in Renhe Township, Yongsheng County of Yunnan Province, China. The plants grow on moist slopes in semi-humid evergreen broad-leaved forests, at an elevation of ca. 2190 m.

Phenology:— Oreocharis synergia has been observed flowering in September to October, and fruiting from September to November.

Etymology:—The epithet “ synergia ” translates to “mutually beneficial co-operation”. The new species is named to commemorate the longstanding relationships between botanic institutes in China and Scotland, going back to 1904 with the first explorations by George Forrest in Yunnan, and subsequent visits to Scotland by eminent Chinese botanists such as Chen Feng-Huai in the 1930s. This tradition continues until today, with regular reciprocal exchange visits between the Kunming Institute of Botany, Chinese Academy of Sciences, and the Royal Botanic Garden, Edinburgh.

Conservation Status:— Oreocharis synergia is only known from one locality in Yongsheng County.The population has around 30 mature plants and about 50 immature plants (and ca. 60 seedlings), with an area of occupancy of around 15 m 2 and area of occurrence of around 200 m 2. The species is provisionally assessed as “Critically Endangered” [CR B2a D] following IUCN Red List Categories and Criteria ( IUCN 2012), because of the restricted range and low number of mature plants. According to recent observations of one author (Rong-Ju Rui), drought, grazing and tree felling are three main threats to its habitat and survival. Observations over two years in 2013 and 2014 indicated a reduction in population size, though this issue needs further observations.

Discussion:— Oreocharis synergia is most similar to O. bodinieri , with which it is here compared and diagnosed against, based on a suite of key features ( Table 1). Another species, O. tubicella Franchet (1899: 249) , also has a yellow near cylindric corolla as O. bodinieri . However, the corolla lobes are slightly reflexed and the leaf base is only slightly cordate to rounded and differs with these characteristics from O. synergia .

Additional specimens:— CHINA. Yunnan Province: Yongsheng County, Renhe Township , on mountain slopes, 26°26 ′ N, 100°56 ′ E, elevation 2194 m, Aug. 24, 2014, with flower buds, Y. M. Shui et al. B2014-256 ( KUN) ; the same locality, Oct. 25, 2013, in fruit, Y. M. Shui et al. B2013-646 ( KUN) .

Figures

FIGURE 1. Oreocharis synergia W.H.Chen, Y.M.Shui & Mich.Möller, sp. nov.A. Habitat; B. Plant; C. Adaxial leaf surface; D. Abaxial leaf surface; E. Brown villous and white indumentum on the abaxial leaf surface; F. Frontal view of corolla; G. Male stage flowers; H. Opened corolla at the male stage, showing filaments with pubescence on proximal half; I. Opened corolla of a immature flower; J. Female stage flowers; K. Opened corolla of female stage flower showing interior corolla surface; L. Exterior surface of opened corolla of female stage flower. Notes: d: disc; s: staminode. Scale bar:A=10 cm, B=2 cm, C= 6 cm, D= 6 cm, E=1 cm; F=1 cm, G=1 cm, H=6 mm, I=7 mm, J=1 cm, K=9 mm, L=9 mm. A–B taken by Rong-Ju Rui, C–L taken by Yu-Min Shui.