Primulina porphyrea X. L. Yu & Ming Li, 2015

Li, Ming & Yu, Xun-Lin, 2015, Primulina porphyrea (Gesneriaceae), a new species from southern Hunan, China, Phytotaxa 208 (2), pp. 157-162 : 158-159

publication ID	https://doi.org/ 10.11646/phytotaxa.208.2.4
persistent identifier	https://treatment.plazi.org/id/03D187EF-FFB7-FF91-B3F9-FAC9FEC58627
treatment provided by	Felipe
scientific name	Primulina porphyrea X. L. Yu & Ming Li
status	sp. nov.

Treatment

Primulina porphyrea X. L. Yu & Ming Li View in CoL , sp. nov. ( Figs. 1 View FIGURE 1 and 2 View FIGURE 2 )

Diagnose: —The new species resembles P. polycephala (Chun) Mich. Möller & A. Weber and P. yangshuoensis Y.G. Wei & Fang Wen in leaf blade shape, indumentum of leaves, peduncle and pedicel. But it readily differs from the latter two in its long petiole, purple leaf abaxial surface, corolla outside densely purple glandular-villous and pubescent, inside puberulent, purple corolla lobes and yellow corolla tube with several reddish-purple stripes, dark yellow filaments, and 3 staminodes.

Type: — CHINA. Hunan Province: Dong’an County, Baiyashi Township, Yanzhu Village , [26°27 ′ 53.13 ″ N, 111°17 ′ 40.50 ″ E], ca. 265 m, on the rock surface or in the caves of a limestone hill. 15 June, 2014, X. L. Yu 140604. (holotype, CSFI!; isotype, CSFI!) GoogleMaps .

Perennial herbs, rhizomes subterete, ca. 2 cm long, ca. 8 mm in diameter. Leaves all basal, thickly papery, broadly ovate or nearly round, 4–8 × 3.5–7 cm; apex obtuse or slightly acuminate, base broadly cuneate, margin entire or slightly serrate, densely covered with white and long pubescence on both surfaces, leaf abaxial surface purple or reddish-purple; lateral veins 3–5 pairs; petiole 5–11 × 0.6 cm, densely covered with white and long pubescence. Cymes 2–7 (not upright, lay down on the rock), unbranched or with 1–2 branches, 2–10-flowered; peduncles 5–12 cm long, densely covered with long and short pubescence; bracts 2, opposite, lanceolate or broadly lanceolate, 1 × 0.2–0.5 cm, apex acuminate, margin serrated, 2–3 pairs, outside densely covered with long pubescence, inside with sparse pubescence. Pedicels 0.8–2.0 cm long, densely covered with short pubescence. Calyx 5-parted nearly to the base, segments lanceolate, 9 × 2 mm, outside puberulent, inside glabrous. Corolla lobes purple, tube pale yellow outside and dark yellow inside. Corolla ca. 4 cm long, outside densely purple glandular-villous and puberulent, inside sparsely short pubescent; tube nearly tubular, having several reddish-purple stripes, ca. 2.5 cm long, 1.5 cm in diameter at the mouth; adaxial lip ca. 1.3 cm long, 2-lobed, lobes ovate, abaxial lip ca. 1.5 cm long, 3-lobed, central one longer, long ovate, lateral ones oval. Stamens 2, adnate to ca. 1.1 cm above the base of the corolla tube, filaments ca. 1 cm long, geniculate from the middle, dark yellow, pubescent and purple glandular-villous; anthers elliptic, ca. 2 mm long. Staminodes 3, lateral ones adnate to ca. 1.3 cm above the base of corolla tube, ca. 6 mm long, glabrous, the central one adnate to ca. 0.1 cm above the base of corolla tube, ca. 2 mm long, glabrous. Pistil ca. 3.0 cm long, ovary ca. 1.0 cm long, style ca. 2.0 cm long, ovary and style densely covered with purple glandular-pubescence and short puberulence; disc circular, white, ca. 1 mm in height, margin entire; stigma 2-cleft, covered with short pubescence. Capsule linear, 3–4 cm × 1–2 mm, densely puberulent.

Distribution and habitat: —The new species is only known from the type locality, Yanzhu Village, Baiyashi Township, Dong’an County, Hunan Province, China. It grows on the rock surface or in the caves and crevices of a limestone hill, at an elevation of 250– 310 m.

Conservation Status: — Primulina porphyrea is only found from its type locality with six small populations. Each population of P. porphyrea is comprised of about 150 mature individuals, and the total number is no more than 1000. These populations are close to human living areas without any protective measures. The habitats are so vulnerable to the impact of human activities. During the several field investigations, we observed the continuing decline of populations as many plants and habitats were destroyed by the flood and other causes. Therefore, according to the IUCN Red List Category ( IUCN 2014), the new species should be regarded as "Critically Endangered, CR B2ab (ii) + C2b" because of its limited populations, localities and vulnerable habitats.

Phenology: —Flowering from May to August, fruiting from July to September.

Etymology: —The specific epithet is porphyrea which means purple or reddish-purple. It’s derived from the color of the leaf abaxial surface.

Similar species: —The new species resembles Primulina polycephala and P. yangshuoensis . But it can be readily distinguished from these two related species by its long petiole and purple leaf abaxial surface, purple corolla lobes and yellow corolla tube with several reddish-purple stripes, dark yellow filaments covered with pubescence and purple glandular-villus, glabrous anthers, and 3 staminodes. Morphological differences among these three related species are provided in Table 1.