Primula xinningensis Wei Zhang bis & J.W.Shao, 2022

Zhang, Wei, Zhang, Yu & Shao, Jian Wen, 2022, Primula xinningensis (Primulaceae), a new species from karst caves in Hunan, China, PhytoKeys 199, pp. 155-166 : 155

Primula xinningensis Wei Zhang bis & J.W.Shao sp. nov.

Figs 3 , 4 , 5

Type.

China. Hunan, Xinning County, Shimen Village , 26°30'27.22"N, 110°40'56.82"E, alt. 458 m, 28 Mar 2016, Wei.Zhang & Jian.Wen.Shao ZW 20160328 (holotype: ANUB!; isotypes: ANUB!, PE!) (Fig. 5 ) .

Diagnosis.

Cotyledon triangular obovate, leaves and scape densely covered with short glandular hairs, flowers long homostyled, corolla lobe apices conspicuously emarginate, pollen sac black.

Description.

Herb biennial, dwarf, densely covered with short glandular hairs. Leaves 9-25 in an open rosette; petiole 1.0-2.0 cm long; leaf blade pinnatisect, 4.0-8.0 cm long, 1.0-2.0 cm wide; pinnae 5-9 pairs, elliptic, margin usually pinnatifid, segments 3-5, apex mucronulate. Scapes 1-8 in each plant, 0.8-2.0 (-2.5) cm tall, carrying one umbel, usually 3 flowers per umbel; bracts linear lanceolate, 2-3 mm long. Pedicel slender, 0.3-0.8 cm. Flowers long homostylous. Calyx narrowly campanulate, 1.0-3.0 mm long, split to the middle; lobes lanceolate, apex acuminate, not outward curvature. Corolla pale red, flowers’ limb 8.0-12.0 mm across, lobes obovate, ca. 2.5 mm wide, apex conspicuously emarginate, corolla tube 5.8-7.0 mm, both stamens and stigma at the mouth of the corolla tube, pollen sac black. Capsule subglobose, 1.0-3.0 mm in diam., dehiscing by valves.

Phenology.

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

Chinese name.

Xīn níng yǔ yè bào chūn (新宁羽叶报春).

Etymology.

The specific epithet ' xinningensis ' refers to the locality, Xinning County, Hunan, China.

Distribution and ecology.

P. xinningensis is known only from Shimen Village, Xinning County, Hunan, China. Growing on the walls or ground of karst caves, at an altitude of 385-487 m. The main accompanied species were Primulina latinervis (W.T.Wang) Mich. Möller & A. Weber. ( Gesneriaceae ), Cyrtomium fortunei J.Sm. ( Dryopteridaceae ) and Pteris multifida Poir. ( Pteridaceae ).

Conservation status.

Vulnerable (VU D1 and D2). This species is endemic to China, Hunan Province, Xinning County, Shimen Village. We only found three populations, all of them near the entrance to the karst caves and each with about 100-250 individuals. The surrounding area is cultivated field with strong human activities. The Extent of Occurrence (EOO) is less than 10 km2 and the known Area of Occupancy (AOO) is less than 0.5 km2. Therefore, the conservation status of this new species is evaluated as ‘Vulnerable’ (VU) as it meets criterion D1 and D2, according to the IUCN Red List Categories and Criteria ( IUCN 2019). In addition, P. shimemensis is a homostylous species. Although Primula containing ca. 500 species, there are only ca. 45 species having monomorphic populations ( Mast et al. 2006). Therefore, the recognition of this new species increases the homostylous species diversity in Primula and can provide valuable material for studying the evolution and maintenance mechanism of distylous flowers.

Additional specimen examined.

China. Hunan: Xinning County, Wanfeng Forest Farm, alt. 450 m, 22 Apr 1995, Lin Bo Luo 00205565 (PE); Xinning County, Wanfeng Forest Farm, alt. 450 m, 22 Apr 1995, Lin Bo Luo 00353811 (IBK); Xinning County, Shuimiao Town, Jiangmu Village, alt. 347 m, 19 Feb 2014, Xun Lin Yu & Hui Zhou 028303 (CSFI); Xinning County, Shuimiao Town, Jiangmu Village, alt. 347 m, 19 Feb 2014, Xun Lin Yu & Hui Zhou 028304 (CSFI).

Figures

Figure 3. Living images of P. xinningensis sp. nov. A, D habitat B, C plant in seedling E plant in flowering.

Figure 4. Morphological characters of P. xinningensis sp. nov. A, B longitudinally dissected of floral tube C infructescence D, F leaves morphology E opened capsule and seeds G leaf surface glandular hairs H leaf margin glandular hairs I rachis glandular hairs.

Figure 5. Holotype of P. xinningensis Wei Zhang bis & J. W. Shao, sp. nov.