Research Article |
Corresponding author: Yi Wang ( 22825818@qq.com ) Academic editor: Bo Li
© 2022 Ze-Huan Wang, Yi Wang, Li Chen, Hua Peng, Zhi-Kun Wu, Guang Guo.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Wang Z-H, Wang Y, Chen L, Peng H, Wu Z-K, Guo G (2022) Primula longipilosa (Primulaceae), a new species from Yunnan, China. PhytoKeys 194: 15-22. https://doi.org/10.3897/phytokeys.194.81335
|
Primula longipilosa from SW Yunnan, China, is described as a species new to science and illustrated. The systematic placement of this new species is also discussed based on an nrITS molecular tree. It is morphologically most similar to P. mollis, but differs from the latter in its racemose inflorescence, green calyx tube, pink to pink rose corolla, stamens at 1/3 length above the base of the corolla tube and applanate globose capsule.
Morphological characteristics, nrITS, phylogenetic analysis, Primula mollis
Primula L. is one of the largest genera of Primulaceae, including ca. 500 species mostly indigenous to the north temperate zone. There are ca. 300 species of 24 sections in China, mostly distributed in western Sichuan, eastern Xizang, and northwestern Yunnan (
As one of the hotspots of biodiversity in China, Yunnan Province has ca. 130 species of Primula distributed all over its range (
During the National Survey of Traditional Chinese Medicine Resources field survey in Gengma County, Yunnan province, we discovered one flowering population of Primula with distinct long white soft multicellular hairs, racemose inflorescences, and pink corolla. After further morphological studies and molecular phylogenetic analysis, we confirmed that it represents a species new to science, which is described and illustrated here.
The morphological description of the new species was based on examining the type specimens (KUN) collected from the type locality and corresponding photos taken in the field. We referred to the keys to sections and species in Flora Reipublicae Popularis Sinicae (
The phylogenetic analysis was mainly based on the recently published framework of Primula (
For the molecular phylogenetic analysis, DNA sequences were newly generated with the protocols described by
As the Bayesian and Maximum Parsimony analysis generated similar results, only the Jackknife 50% majority-rule consensus tree is presented here (Fig.
Jackknife 50% majority-rule tree of selected species from Primula (Primulaceae) based on the nrITS region, focusing on the subgen. Auganthus and the subgen. Carolinella. The MP jackknife support (JK) values are shown above the branches, and the BI posterior probabilities (PP) are given below the branches.
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!).
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
Comparison of the morphological characters between Primula longipilosa and P. mollis.
Character | P. longipilosa | P. mollis |
---|---|---|
Leave blade | margin undulate | margin sinuate-lobulate and denticulate-crenulate |
Inflorescence | racemose, shorter than or almost equal to the leaves | umbellate, umbels 3–10, superimposed, significantly longer than leaves |
Pedicel | covered with dense hairs | covered with sparse hairs |
Calyx | tube green | tube deep red |
Corolla | pink to pink rose | deep red |
Stamens of Pin flowers | stamens at 1/3 length above the base of corolla tube | stamens at the middle of the corolla tube |
Capsule | applanate globose | Ellipsoid |
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.
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.
Flowering and fruiting from July to August.
The specific epithet refers to the impressive long spreading white soft multicellular hairs on the whole plant.
Simplified Chinese: 长毛报春; Chinese Pinyin: Chángmáo Bàochūn.
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.
According to the keys of Primula in Flora Reipublicae Popularis Sinicae (
The molecular phylogenetic study also showed that P. longipilosa had a close relationship with the species of the sect. 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
The authors are grateful to Dr. Y. Luo for her illustrations and Dr. F. Zhao for his help in finding the old literature. This study was supported by the National Natural Science Foundation of China (grant no. 31500168) and the specific funds for the Fourth National Survey on Chinese Material Medica Resources (GZY-KJS-2018-004).