Primulina jiangyongensis X. L. Yu & Ming Li, 2014

Li, Ming, Yu, Xun-Lin & Ma, Qi-Xia, 2014, Primulina jiangyongensis (Gesneriaceae), a new species from Southern Hunan, China, Phytotaxa 177 (4), pp. 244-248 : 244-247

Primulina jiangyongensis X. L. Yu & Ming Li , sp. nov. (See Figure 1 and Figure 2 ).

Diagnosis: —The new species is similar to P. lutea (Yan Liu & Y. G. Wei) Mich. Möller & A. Weber in having yellow flowers, but differs in both surfaces of leaves densely with appressed bristles (not with appressed pubescence), peduncle and bracts densely spreading villous (not only densely appressed pubescent), pedicel densely glandular-villous and pubescent (not densely glandular-pubescent), corolla lower lip with several dark purple stripes (not unmarked), filaments dark purple (not light yellow), and staminodes 3 (not 2).

Type: — CHINA. Hunan Province: Jiangyong Xian, Lanxi Yaozu Zizhixiang , [25°06′00.26″N, 111°10′42.59″E], elevation ca. 281 m, on the rock of a limestone hill, 5 May, 2012, X. L . Yu 12051501 (holotype, CSFI!; isotypes, CSFI!, IBSC!)

Perennial herbs, rhizomes inconspicuous. Leaves all basal, opposite; petiole semicircular and flattened, 2–5 cm long, 5–8 mm thick, densely villous and pubescent; blade thickly leathery, ovate or broadly ovate, 4–12 × 3.8–10.5 cm, apex slightly acuminate or obtuse, base cuneate or truncate, margin entire, densely covered appressed bristles on both surfaces, lateral veins 3–4 pairs, inconspicuous. Cymes axillary, unbranched or with 1–2 branches, (2–)4–11-flowered; peduncles 7–18 cm long, densely spreading villous and pubescent; bracts 2, opposite, ovate or oval, apex slightly acuminate, 3–5 × 1.8–3 cm, margin repanded, outside purple or green, densely villous, inside with sparse pubescence, 7–10-veined, conspicuous. Pedicels 1.2–1.5 cm long, densely glandular-villous. Calyx 5-parted to the base, segments narrowly linear, 4–6 × 0.8 mm, outside glandular-villous and puberulent, inside sparsely pubescent. Corolla yellow, ca. 4 cm long, outside densely glandular-pubescent and puberulent, inside yellowish-brown on the throat, sparsely glandular-pubescent and puberulent, tube thickly infundibuliform, ca. 2.8 cm long, 1.5 cm in diameter at the mouth, limb distinctly 2-lipped, adaxial lip ca. 0.8 cm long, 2-lobed, lobes ovate, abaxial lip with 9–14 dark purple stripes, ca. 1.3–1.6 cm long, 3-lobed, central one longer, long ovate, lateral ones oval. Stamens 2, adnate to ca. 1.8 cm above the base of the corolla tube, filaments ca. 1 cm long, geniculate from the middle, deeply atropurpureus, sparsely pubescent; anthers elliptic, ca. 4 mm long; staminodes 3, lateral ones adnate to ca. 1.5 cm above the base of corolla tube, ca. 5 mm long, densely pubescent, apex bended, the central one adnate to ca. 0.8 cm above the base of corolla tube, ca. 2 mm long, pubescent. Disc diagonal, ca. 3 mm in height, margin serrate. Pistil ca. 3.3 cm long, densely glandularpubescent and puberulent. Ovary ca. 2 cm long, style ca. 1.3 cm long, ovary and style densely glandular-pubescent and puberulent; stigma 2-cleft. Capsule linear, 4–8 cm × 1–2 mm, densely glandular-vilolus and puberulent.

Distribution:— The new species is only known from the type locality, Lanxi Yaozu Zizhixiang [25°06′00.26″N, 111°10′42.59″E], elevation ca. 281 m, Jiangyong Xian, southern Hunan, China.

Ecology & Habitat: —The new species grows in wet places or cracks in the rock in limestone areas, mainly in the subtropical evergreen broad-leaved forest at elevation of 260– 340 m. Its habitat is dominated by several trees, e.g. Cyclobalanopsis glauca , Radermachera sinica , Lagerstroemia subcostata , Acer coriaceifolium , Osmanthus fragrans , Boniodendron minus , Chukrasia tabularis , and some shrubs, e.g. Flueggea virosa , Sophora franchetiana , and a few herbaceous species as well, e.g. Pilea cavaleriei , Castilleja pallida .

Phenology: —Flowering in May, fruiting from May to June.

Etymology: —The name of this new species is derived from its locality, i.e. Jiangyong Xian, Hunan Province, China.

IUCN Red List Category: — Primulina jiangyongensis is only found from its type locality, Lanxi Yaozu Zizhixiang [25°06′00.26″N, 111°10′42.59″E], elevation ca. 281 m, Jiangyong Xian , southern Hunan, China. The population is not in a protected area, nature reserve or park, and there is no any protective measures. Its habitat is vulnerable and subject to the destruction from human activities. There is only one population with about 100 individuals. Thus according to the IUCN Red List Criteria ( IUCN 2010), the new species should be acted as Critically Endangered ( CR B2 a; C2 b) because of its limited populations and vulnerable habitat .

Similar species: —Morphologically, Primulina jiangyongensis resembles P. lutea since both species are perennial herbs, with basal leaves, entire leaf blade margins, a pair of large bracts and yellow flowers. But it can be readily distinguished from P. lutea by its inconspicuous rhizomes, thickly leathery, broadly ovate leaves, both surfaces with densely appressed bristles, peduncle and bracts densely villous and pubescent, pedicel with dense glandular-pubescence, corolla with the lower lip entire having several dark purple stripes, and filaments dark purple, with sparse appressed puberulence. The contrasting characters between P. jiangyongensis and P. lutea are shown in Table 1.

Figures

FIGURE 1. Primulina jiangyongensis sp.nov. (drawn by Jing Tian): (A)plant with flowers, (B)opened corolla, (C)stamens, (D) pistil.

FIGURE 2. Primulina jiangyongensis sp.nov.: (a)habitat, (b)flowering plant in the wild, (c)flowering plant in greenhouse, (d)leaves, (e)bracts, (f)flowers, (g)corolla, stamens showing staminodes, pistil and disc, (h)capsule.