Paraboea zunyiensis T.Deng, F.Wen & R.B.Zhang, 2023

Deng, Tan, Wen, Fang, Xie, Da-Jun, Wei, Ruo-Xun, He, Lin, Dou, Quan-Li, Qian, Zheng-Min & Zhang, Ren-Bo, 2023, Paraboea zunyiensis (Gesneriaceae), a new species from north Guizhou, China, PhytoKeys 235, pp. 21-29 : 21

Paraboea zunyiensis T.Deng, F.Wen & R.B.Zhang sp. nov.

Figs 1 , 2

Diagnosis.

Paraboea zunyiensis morphologically resembles P. crassifolia , but can be distinguished by the shorter staminodes (<1 mm vs. 2-2.5 mm in P. crassifolia , following the same order), filaments (ca. 1 mm vs. (3-) 5.5-7 mm) and anthers (1.5-2.3 mm vs. 2.5-3 mm), calyx lobe shape (triangular ovate vs. narrowly triangular to linear), the outer calyx indumentum (tomentose vs. puberulent or velutinous), and the ovary length (ovaries longer than the styles vs. ovaries shorter than the styles).

Type.

China, Guizhou Province, Zunyi City, Maoli Town, Xiazhai Valley , elev. ca. 1000 m, 27.36986425°N, 107.05679454°E, growing on the Karst rocks alongside the stream. 15 April 2023, Ren-Bo Zhang ZRB2493 (fl.) (holotype: IBK!, isotypes: ZY!) and 27 May 2023 Ren-Bo Zhang ZRB2498 (fr.) (paratype: ZY!) .

Description.

Herbs, stemless. Leaves basal, petiole 0.8-1.5 cm long; leaf blade spathulate or oboval-oblong, 3.5-12 (-25) × 1-3.5 (-8) cm, thick papery to leathery, adaxially cobwebby-woolly, glabrescent, abaxially densely cobwebby-woolly to pannose, base attenuate to cuneate, margin crenate or subentire, involute, apex rounded or acute; lateral veins 4-7 on each side of midrib. Cymes 1-2, axillary, each cyme 3-7 branched and 9-22 flowered; peduncle 2-6 cm long, ca. 1.5 mm in diam, cobwebby-woolly, glabrescent from upper part; bracts 2, opposite, linear, 2-3 × 0.6-0.9 mm, outside cobwebby-woolly. Pedicel 1-2 cm long, cobwebby-woolly. Calyx ca. 3 mm long, 5-sect from near base; segments triangular ovate, 1-2 × ca. 0.5 mm, outside brown tomentose. Corolla blue-purplish, ca. 1.5 cm long, subglabrous on both sides; tube 7-8 mm long; adaxial lip ca. 3 mm long, lobes 2-3 × ca. 5 mm; abaxial lip ca. 7 mm long, lobes 3-4 × 5-6 mm. Stamens 2, filaments ca. 1 mm long, glabrous; anthers 1.5-2.5 mm long; staminodes 2, ca. 0.8 mm long. Pistil glabrous; ovary 4-6 mm long; style 3-5 mm long; stigma capitate. Capsule spirally twisted, 2-4 cm long, glabrous. Seeds 0.5-0.7 × 0.2-0.3 mm, reticulate, apiculate or cuspidate at both ends. Fl. Apr-May. Fr. May-Jun.

Phenology.

Flowering occurs from April to May, and fruiting occurs from May to June.

Etymology.

The specific epithet is derived from the type locality, Zunyi City, Guizhou Province, China.

Vernacular name.

The Chinese name proposed here is “遵义蛛毛苣苔”. Phonetically, it is "Zūn yì zhū máo jù tái”.

Distribution and ecology.

The new species is endemic to Guizhou Province and is known only from the type locality, Xiazhai Valley in Zunyi City. It grows on the steep Karst cliff in a valley, at an altitude ca. 1000 m.

Conservation status.

Paraboea zunyiensis is known only from the type locality, with the individuals estimated to be over thousands of plants. Considering the narrow distribution area, we proposed it as “NT” (near threatened) according to the guidelines for using the IUCN Red List Categories and Criteria ( IUCN Standards and Petitions Committee 2022).

Taxonomic and phylogenetic notes.

The aligned matrix of ITS and trnL-F sequences comprised 1562 characters. The three outgroup species are clearly distinguishable from the Paraboea species (Fig. 3 ). P. hainanensis (Chun) B.L.Burtt is quite different and other Paraboea species form two big clades, which matches a previous study ( Guo 2016). Although P. zunyiensis and P. crassifolia are in the same branch (BI = 100%), they are not clustered together and they can be morphologically distinguished from the traits presented in Table 2 . P. zunyiensis is clustered with P. neurophylla (Hance) B.L.Burtt and P. trisepala W.H.Chen & Y.M.Shui (BI = 100%). P. crassifolia and P. velutina (W.T.Wang & C.Z.Gao) B.L.Burtt are clustered as a sister group (BI = 95%) and then clustered with P. dictyoneura (Hance) B.L.Burtt.

Figures

Figure 1. Line drawing of Paraboea zunyiensis T. Deng, F. Wen & R. B. Zhang, sp. nov. A flowering plant B corolla C opened corolla D adaxial leaf surface E abaxial leaf surface F calyx G bracts H pistil I capsules J seed K fertile stamens L staminodes. Drawings by Tan Deng from the type specimens.

Figure 2. Living or re-watered photographs of Paraboea zunyiensis T. Deng, F. Wen & R. B. Zhang, sp. nov. A habitat B flowering plant C cyme D flowers E fruiting plant F upward view of the plant G pistil H stigma and style I fertile stamens J staminodes K calyx L bracts M capsules N seeds (Photographed by T. Deng and R. B. Zhang)

Figure 3. Bayesian phylogenetic tree of Paraboea including P. zunyiensis based on the combined data from ITS and trnL-F, with the branch lengths indicating the nucleotide substitution rates and the posterior probabilities are shown beside the branches.