Mussaenda campanulata, T. T. Duan et D. X. Zhang, 2016

Duan, Tingting, Li, Shijin & Zhang, Dianxiang, 2016, Mussaenda campanulata (Rubiaceae), a new monomorphic species from China, Phytotaxa 265 (2), pp. 164-168 : 165-167

Mussaenda campanulata, T. T. Duan et D. X. Zhang , sp. nov. ( Fig. 1 . & Fig. 2 .)

TYPE:— China. Yunnan, Jinping, Fenshuiling Nature Reserve , on forest edge, 22°39’35.44” N, 102°54’37.59” E, ca. 1600 m, 26 April 2015, S. J. Li 3994 (Holotype, IBSC) .

Haec species a Mussaenda shikokiana Makino habitibus lianis, corollis campanulatis, petalis flavescentibus differt.

Climbing shrubs or lianas, branches terete, young stems covered with sparse strigillose hairs. Stipules 5–7 mm long, present or deciduous, triangular, covered with moderately hairs, deeply 2-lobed, lobes acute to acuminate. Petiole 4–8 mm long, hirsute or villous. Leaves blade drying papery, pale green, elliptical or oblanceolate, 5–9 cm long, 3–5 cm wide, base cuneate to obtuse, apex acute to acuminate, both surfaces sparsely strigillose on lamina and moderately to strigillose to hirsute along principal veins, secondary veins 5–7 pairs, without domatia, tertiary venation reticulate. Inflorescences subcapitate to congested-cymose, 1–3 × 1–3 cm, terminal and often in uppermost leaf axils, sparsely to densely strigillose, hirsute, sessile to subsessile, bracts narrowly triangular to lanceolate, 2–7 mm, obtuse to acuminate or 2- or 3-parted. Flowers pedicellate, 3–7 mm long. All of the five calyx lobes are subequal, narrowly triangular to lanceolate, sparsely strigillose; hypanthium portion ellipsoid to turbinate, 2–5 mm; lobes linear to narrowly triangular, 3–12 mm. Corolla light yellow, campanulate-funnelform; densely yellow clavate pubescent in throat, tube 7–11 mm; lobes ovate, 2–3 mm, abruptly acuminate, stamens 5, inserted in the middle-upper part of corolla tube, filaments 3–5 mm long, glabrate, anthers linear, 3–4 mm long; Style glabrate, stigma bifid-lamella equal, lamella oblong. Baccae are subglobose, ca. 6 × 6 mm, moderately to densely strigose, sparsely lenticellate, calyx limb deciduous. Seeds numerous, minute, reticulate, bearing on axile placentas.

Distribution and habitat:— Mussaenda campanulata is so far only known from the Fenshuiling Nature Reserve, Jinping County, Yunnan province in China. The type locality, however, is only ca. 8 and 79 kilometers away from the borders to Vietnam and Laos respectively, its occurrence in the neighboring countries is thus expected. It grows in edge of the moist forests at an altitude of 1500–1700 m.

Etymology:—The specific epithet derived from the shape of corolla.

Paratypes:— China. Yunnan, Jinping, Fenshuiling Nature Reserve , in the moist soil of forest edge, 22°39’35.1” N, 102°54’37.7” E, in 4 June 2015, T.T. Duan 841, T.T. Duan 842, T.T. Duan 843 ( IBSC) .

Figures

FIGURE 1. Mussaenda campanulata. A. Dense cymose inflorescens. B. Fruits. C. Flowers, the left showing an opening flower, the right showing the level of stigma and stamens in bud, scale bar=2.5 mm. D. Pollen, showing polar view, scale bar=5 μm. E. Pollen, showing aperture and aperture membrane, scale bar=1μm.

FIGURE 2. Mussaenda campanulata.A.A flowering branch. B.A fruiting branch, scale bar=1 cm. C. Flower, scale bar=5 mm. D. Stigma, scale bar=5 mm. E. Corolla and stigma, scale bar=4 mm. Flowering materials from the holotype, S. J. Li 3994. Fruiting materials from T. T. Duan 841.