Primulina niveolanosa F.Wen, S. Li & W.Chuen Chou, 2019

Li, Shu, Xin, Zi-Bing, Chou, Wei-Chuen, Huang, Yi, Pan, Bo, Stephen Maciejewski, & Wen, Fang, 2019, Five new species of the genus Primulina (Gesneriaceae) from Limestone Areas of Guangxi Zhuangzu Autonomous Region, China, PhytoKeys 127, pp. 77-91 : 84-87

Primulina niveolanosa F.Wen, S. Li & W.Chuen Chou sp. nov. Fig. 4

Diagnosis.

Primulina niveolanosa most closely resembles P. repanda (W.T. Wang) Y.Z. Wang ( Fig. 6 D ) ( Wang 1981, Wang et al. 2011, Weber et al. 2011) in having similarly shaped leaf blades, but differs in their indumentum of the leaf blades (both surfaces spreading densely long white villous to lanate in P. niveolanosa vs. appressed puberulent to villous in P. repanda ; same order as following), number of bracts (3, whorled vs. 2, opposite), shape of bracts (narrowly oblong to broadly oblanceolate vs. lanceolate-linear to subulate), shape of calyx lobes (linear to narrowly oblanceolate vs. narrowly triangular), corolla length (1.5-1.8 cm long vs. ca. 8 mm long).

Type.

CHINA. Yizhou city, Beiya Town , Jiucai village, 24°24'N, 108°24'E, 181 m a.s.l., growing on the surface of a moist cliff at the edge of a village, 3 Apr 2018, Chou Wei Chuen et al. CWC171116-01 (holotype: IBK!, isotypes: IBK!)

Description.

Perennial herbs. Rhizome cylindrical, 3-15 mm long, 1.5-3 mm in diam. Leaves numerous, 16-40 or more, all basal, petiolate; petiole green, oblong-oblate, 4-8 cm long, 6-15 mm in diam., spreading appressed white pubescent to lanate; leaf blade pale green to green, fleshy to thickly chartaceous, herbaceous when dried, narrowly oblong, narrowly oblanceolate to oblong-elliptic, 5-10 × 2.5-4.5 cm, apex obtuse and occasionally rounded, base gradually attenuated to form petiole, margin entire, undulatet to crenate, both surfaces densely villous to lanate with long, spreading white hairs, lateral veins 4 or 5 on each side, slightly impressed adaxially and apparently prominent abaxially. Cymes axillary, 6-12 per plant, 2-4-branched, 16-36-flowered per cyme; peduncle 15-25 cm long, 2.5-3.5 mm in diam., green, densely white villous and lanose; bracts 3, whorled, brownish green, margin entire to undulate, apex acuminate to acute, adaxially white pubescent, abaxially nearly glabrous, lateral ones bigger, ca. 15 × 6 mm, narrowly oblong to broadly oblanceolate, central one smaller, ca. 15 × 3.5 mm; pedicel 1-1.5 cm long, ca. 1 mm in diam., indumentum same as pedicel; pedicel green, 1-2.5 cm long, 1-1.5 mm in diam., densely white pubescent. Calyx 5-parted nearly to base, lobes green to brownish green, linear to narrowly oblanceolate, 5-7 × ca. 2 mm, margin entire, outside white puberulent, inside nearly glabrous. Corolla pale pink to white, inside with two dark pink to pinkish orange stripes, 1.5-1.8 cm long, 5-7.5 mm in diam. at mouth, outside and inside glabrous; tube infundibular, pale pink, 1.1-1.3 cm long, 4.5-5.5 mm in diam. at the middle, 1.3-1.8 mm in diam. at base; limb distinctly 2-lipped, adaxial lip 2-lobed to over middle, lobes oblong to rounded, apex rounded, 3.5-4 × ca. 4 mm, abaxial lip 3-lobed to over middle, lobes oblong to rounded, apex rounded, 4-4.5 × ca. 4 mm. Stamens 2, adnate to ca. 1.8-2.2 mm above corolla tube base, filaments 1.8-2.3 mm long, geniculate at 1/3 from the bottom, glabrous, anthers elliptic or reniform, ca. 1 mm long, ca.0.5 mm in diam. per anther, white beard; staminodes 3, glabrous, lateral ones adnate to 1.7-2 mm above corolla tube base, white to translucent, ca. 2 mm long, apex capitate, central one adnate to ca. 1.6 mm above corolla tube base, capitate. Disc annu lar, glabrous, ca.0.6 mm in height, margin entire to sinuate. Pistil ca. 8 mm long, ovary ovoid, ca. 2 × 1.3 mm, densely eglandular lanose; style ca. 6 mm long, ca. 0.3 mm in diam. at the middle, the lower part of style sparsely eglandular-puberulent but the upper half part of style nearly glabrous; stigma obtrapeziform, ca. 0.5 mm long, apex 2-lobed. Capsule ovoid, glabrous, valvate dehiscence when mature, 4-4.5 × ca. 3 mm.

Phenology.

Flowering from March to April; fruiting from April to May.

Etymology.

The specific epithet, ' niveolanosa ', consists of two parts. The first part of " niveo ", comes from the Latin word, ' niveus ', and means as white as snow, or snow-white; the second half, ' lanosa ', is from the Latin, ' lanosus, lani -', meaning with lanose or villous hairs. Thus, the scientific name refers to the plants seemingly covered with snow because of the indumentum of snowy lanose hairs. The Chinese name is “Mián Máo Xiáo Huā Jù Tái” (绵毛小花苣苔).

Distribution and habitat.

Primulina niveolanosa is currently known only from the type locality: a single population with ca. 100 individuals, and although it might be endangered, more surveys are needed to clarify its conservation status. The species is only known growing on the surface of a moist cliff along the edge of a village.

Provisional IUCN conservation assessment.

About 100 mature individuals have been recorded and confirmed, growing on a wet rock surface under evergreen broad-leaved forest on a limestone hill. Because the local government of Yizhou city is planning to develop a scenic spot project at this place, the habitat of this new species is likely to be subjected to human activities. Thus, based on currently available information, P. niveolanosa should be considered as 'Critically Endangered’ (CR): B1+2ab(V); C2b, following the IUCN categories and criteria ( IUCN 2012).

Figures

Figure 4. Primulina niveolanosa F. Wen, S. Li & W. Chuen sp. nov. A plant in flower, cultivated in GCCC B cyme with flowers C close look of cyme and flowers D front view of corolla E lateral view of corolla F lateral view of corolla, bracts and bracteoles G dorsal view of corolla H lateral view of corolla with scale I opened corolla for showing stamens and staminodes J pistil with two calyx lobes for showing ovary and style and their indumentum K adaxial surface of calyx lobes. Photographed by Fang Wen, charted by Wen-Hua Xu.

Figure 6. The morphologically similar congeners of the five new species of Primulina 1 habit 2 flowers. A P. leprosa, the congener of P. purpureokylin B P. gongchengensis, the congener of P. persica C P. renifolia, the congener of P. cerina D P. repanda, the congener of P. niveolanosa E P. longgangensis, the congener of P. leiyyi. Photographed by Fang Wen, charted by Wen-Hua Xu.