Primula jiaozishanensis Z.K.Wu, W.H.Yang & Yuan Wu, 2023

Wu, Yuan, Yang, Wu-Hai & Wu, Zhi-Kun, 2023, Primula jiaozishanensis (Primulaceae), a new species in Primula sect. Petiolares subsect. Davidii from Yunnan, China, PhytoKeys 227, pp. 25-33 : 25

Primula jiaozishanensis Z.K.Wu, W.H.Yang & Yuan Wu sp. nov.

Figs 1 , 2 , 3A, D

Diagnosis.

The new species most resembles P. esquirolii and P. sinoexscapa , sharing similar leaves with a more or less rugose surface and short or almost obsolete scape at flowering time. However, the new species differs from the latter two mainly in its long and stout rhizome with 1-3 rosettes, smaller leaf blades with shorter petioles, shorter and stouter pedicels, and larger flowers (Figs 1 - 3 ). The main morphological distinctions between P. jiaozishanensis , P. esquirolii and P. sinoexscapa are summarized in Table 1 .

Type.

China. Yunnan: Dongchuan District, Luoxue xiang, Jiaozi Snow Mountain . 26°9.77'N, 102°56.7'E, 3990 m alt., 1 May 2017 (fl.), Zhikun WU ZKWu2017050 (holotype: KUN!; isotype: KUN!) .

Description.

A perennial hairy robust, dwarf herbaceous, efarinose, with a long stout rhizome and numerous fibrous roots, rhizome 3-4 cm long, ca. 0.5 cm in diameter; at flowering time girt at the base by ovate to oblong paleaceous bud scales, scales 1.5-1.8 cm long, 0.4-0.6 cm broad, acute at the apex, outer surface with a sparse covering of long multicellular hairs. Leaves forming 1-3 rosettes, leaves of current year not well-developed at anthesis, leaves of previous year at flowering time 2-4 cm long including the petiole, 1.5-2.5 cm broad, spatulate or elliptic-obovate, obtuse or rounded at the apex, gradually tapering into the winged petiole; petiole 0.5 to 1 cm, 1/4 as long as leaf blade, stout with a thick covering of long multicellular hairs; lamina coriaceous, adaxially bullate, covered with sparse white long hairs, abaxially with multicellular hairs along veins, margin with regular sparsely acute serrate. Scape at flowering time almost obsolete or to 1 cm, usually solitary, covered by bud scales, with a thick covering of long multicellular hairs, usually 1 flowered or occasionally 2 flowered. Bracts linear-lanceolate, 3-6 mm long, glabrous; pedicel 1-3 mm, shorter than bract, with a thick covering of long multicellular hairs. Flower heterostylous; calyx campanulate, 6-8 mm long, puberulous, parted to 1/2 of its length, lobes ovate to ovate-lanceolate, apex obtuse or occasionally serrate; corolla funnel-shaped, purplish blue or violet, tube 15-20 mm long, usually twice the length of the calyx, limb 30-45 mm wide, lobes obcordate, 13-18 mm long, apex deeply emarginate. Pin flowers: corolla tube 14-16 mm long, stamens ca. 7 mm above the base of the corolla tube, style 14-16 mm long. Thrum flowers: corolla tube 16-20 mm; stamens 16-18 mm above base of corolla tube, style ca. 8 mm long. Capsule unknown.

Distribution and ecology.

Primula jiaozishanensis is only known from the type locality on Jiaozi Snow Mountain in Dongchuan District, Yunnan, China. The plant grows in the open alpine meadow (Fig. 1 , Map 1 ).

Phenology.

Flowering occurs from April to May.

Etymology.

The specific epithet of the new species is taken from the Chinese Pinyin, “Jiaozishan”, the name of the mountain in Northern Yunnan, China, where the type specimen was collected (Map 1 ).

Vernacular name.

Chinese mandarin: jiao zi shan bao chun (轿子山报春).

Provisional Conservation status.

Critically Endangered (CR B2ab(iii)). The authors have conducted field surveys several times in the type locality and adjacent districts (e.g., Luquan, Qiaojia and Huize) for this new species, and discovered only one population of Primula jiaozishanensis , with approximately 100 adult individuals, distributed over about 100 m2 in the type locality. This site is in a dry alpine meadow; the new species grows very close to the path for visitors and faces a strong threat from grazing and human activities. Its status should therefore be of concern and addressed by further investigations.

We estimated the extent of occurrence of the species to be less than 10 km2. Over the last five years, we have observed a steady decline in the territory area of the habitat due to road construction and grazing. Considering the present field information and IUCN categories of threat ( IUCN Standards and Petitions Committee 2022), this species should be included in the category Critically Endangered (CR B2ab(iii)).

Additional specimens examined

(paratypes). The same locality as holotype, 8 May 2020 (fl.), Zhikun WU ZKWu 2020045 (KUN!) .

Figures

Figure 1. Primula jiaozishanensis sp. nov. A-I A habitat B, C habit in flowering D leaves, left: upper surface, right: lower surface E bud scales, left: outer surface, right: inner surface F calyx, left: outer surface, right: inner surface G flower shape H corolla lobes, left: upper surface, right: lower surface I dissected corolla showing anthers and stigmas, left: pin flower, right: thrum flower. Photographed by Z. K Wu.

Map 1. Location of the population of Primula jiaozishanensis in Dongchuan District, Yunnan.

Figure 2. Primula jiaozishanensis sp. nov. A habit B leaves, left: upper surface, right: lower surface C bud scales, left: outer surface, right: inner surface D calyx, left: outer surface, right: inner surface E bract F flower, long style (pin) G flower, short style (thrum). Drawn by Ms. Xiang-Li Wu.

Figure 3. Primula jiaozishanensis and two of its allies A holotype specimen of P. jiaozishanensis (ZKWU 2017050, KUN, specimen number KUN 1576215) B the possible type of P. esquirolii (Martin, L. and Esquirol, J., E, specimen number E 00024325) C paratype of P. sinoexscapa from its type locality (M. K. Li 3530, WUK, specimen number WUK 0275821) D P. jiaozishanensis E P. esquirolii F P. sinoexscapa. D-F photographed by Z. K Wu from their type locality.