Primula longipilosa Ze H. Wang & H. Peng, 2022

Wang, Ze-Huan, Wang, Yi, Chen, Li, Peng, Hua, Wu, Zhi-Kun & Guo, Guang, 2022, Primula longipilosa (Primulaceae), a new species from Yunnan, China, PhytoKeys 194, pp. 15-22 : 15

Primula longipilosa Ze H. Wang & H. Peng sp. nov.

Figs 2 , 3

Type.

China, Yunnan Province, Gengma County, Gengma Town, new Aiguo Village . 23°39.91'N, 99°32.44'E, alt. 1384 m, 31 July 2020, Gengma TCM Resources Survey Exped. 5309260482 (holotype: KUN!, isotypes: KUN!) .

Diagnosis.

Primula longipilosa is most similar to P. mollis in the long soft multicellular hairs all over the plant, the shape of their leaves and corolla. But it differs from the latter mainly in its racemose inflorescence, green calyx tube, pink to pink rose corolla, stamens of the pin flowers at 1/3 length above the base of corolla tube, and applanate globose capsule. The main morphological differences between P. longipilosa and P. mollis are summarized in Table 1 .

Description.

Perennial herbs with several robust fibrous roots. The whole plant is covered with long white soft multicellular hairs. Stem extremely shortened, inconspicuous. Leaves all rising from the root, forming a rosette; petiole 5-20 cm, clothed with long spreading soft multicellular hairs, slightly sheathing at the base; leaf blade cordate to broad cordate, 3.5-19 cm long, 4-16 cm wide, covered with white soft multicellular hairs on both sides; apex obtuse, base cordate or deeply cordate, margin undulate; basal veins usually 3-5, lateral veins 5-6, all raised abaxially and further branched to form reticulate fine veins. Scapes 7-17 cm long, 2-3 rising from the middle of the rosette leaves, shorter than or almost equal to the leaves, densely covered with long soft multicellular hairs, each scape has 7-25 flowers arranged in a racemose inflorescence, or sometimes several nearby flowers grow close to each other to form an umbel in some part of the inflorescence; bracts narrowly lanceolate, 0.5-1 cm long, with long soft multicellular hairs. Pedicel 1.5-2.5 cm, extended to 4 cm in fruit, densely covered with long soft multicellular hairs. Flowers heterostylous. Calyx narrowly campanulate, green, 6-10 mm, covered with long soft multicellular hairs abaxially, parted to the middle; lobes triangulate to ovate-triangulate; veins 3-5. Corolla pink to pink rose, with long soft multicellular hairs outside; tube 1-1.2 cm long; limb ca.1.5-2 cm in diameter; lobes obcordate, ca. 9 mm, with several rays sending out from the mouth, which is prominent especially at the base, bifid at the apex; pin flowers: stamens at ca 3 mm above the base of corolla tube, their style ca 8 mm long; thrum flowers: stamens at 2/3 length of corolla tube, ca. 1 cm above the base of corolla tube, their style ca 2 mm. Ovary applanate globose, stigma a depressed globose disc. Capsule applanate globose, ca. 5 mm in diameter, hidden by the persistent calyx, 5-toothed split.

Distribution and habitat.

Primula longipilosa is currently encountered and seen growing on the moist mountain slopes along the valley forest margin near the new Aiguo Village, Gengma County, Yunnan Province, China.

Phenology.

Flowering and fruiting from July to August.

Etymology.

The specific epithet refers to the impressive long spreading white soft multicellular hairs on the whole plant.

Vernacular name.

Simplified Chinese: 长毛报春; Chinese Pinyin: Chángmáo Bàochūn.

Threat status.

Currently, the authors have discovered only one population of Primula longipilosa with ca. 30 individuals from the type locality. Some plants grow very close to the path to face a stronger strength from human activities. However, as the authors conducted no detailed field survey for this new species in the adjacent districts, whether some other populations exist remains unknown. Considering its localized distribution in SW Yunnan, its status should nevertheless be of concern and addressed by further investigations.

Relationship with related species.

According to the keys of Primula in Flora Reipublicae Popularis Sinicae ( Hu 1990) and Flora of China ( Hu and Kelso 1996), Primula longipilosa should be ascribed to the sect. Primula Cortusoides by a combination of the following morphological characters: long soft multicellular hairs all over the plant; leaves with long stipe, base cordate or deeply cordate, margin undulate; Flowers heterostylous; Calyx narrowly campanulate, veins 3-5; Corolla pink to pink rose.

The molecular phylogenetic study also showed that P. longipilosa had a close relationship with the species of the sect. Primula Cortusoides . It was most closely related to P. mollis of this section in terms of the long soft multicellular hairs all over the plant, the shape of their leaves and corolla, and also their distribution area. As there are some discrepancies or feature omissions in the description of P. mollis in different flora, we referred to its protologue and color illustration for the morphological comparison between them. The detailed morphological comparison between both species is shown in Table 1 .

Figures

Figure 2. Primula longipilosa sp. nov. A habit B-C pin flowers D-E thrum flowers F capsule with dissected calyx. Drew by Dr. Yuan Luo.

Figure 3. Primula longipilosa sp. nov. A habit B upper face of leaves C lower face of leaves D hairs on the petiole E racemose inflorescence F-G thrum flowers H pin flower I front side of corolla J calyx in late-flowering K capsule with dissected calyx. Photographed by Li Chen.