Allium zhouquense Z.F.Bai & Xue L.Chen, 2024

Bai, Zengfu, Zhang, Zhihua, Chen, Xuelin & Zhang, Ji, 2024, Allium zhouquense (Amaryllidaceae) - a new species from Gansu, China, Phytotaxa 663 (3), pp. 165-170 : 166-169

Allium zhouquense Z.F.Bai & Xue L.Chen , sp. nov.

( Figs. 1–2 ).

Type: — CHINA. Gansu: Zhouqu County, Bailongjiang Chagangliang Provincial Nature Reserve , under a deciduous broadleaf forest or thicket, elec. 2800–3041.5 m, 27 August 2023, Zengfu Bai & Xuelin Chen 2023008 (holotype NWTC; isotypes NWTC, GAUF) .

Diagnosis:—It resembes both A. plurifoliatum and A. paepalanthoides , and can be distinguished from them by the following combination of traits: 1) outer filaments with a broadened base and two top shallow cracks, and inner filaments with one basal tooth on both sides; 2) pedicels 6–8 times the length of perianth; 3) the position of leaf sheath covering 1/3 to 1/2 of scape height; and 4) strigose along leaf edge, leaf sheath, and midvein. Detailed comparison among the three species is summarized in Table 1 .

Description: —Herbs perennial, with onion-like odor. Bulb solitary, rarely paired, cylindric, measuring 0.5–1 cm in diameter, with irregularly split grayish-brown membranous tunics. Leaves are linear, shorter than scape, 13–16 × 0.3–0.6 cm, flat, clearly 1-keeled abaxially, margin setose-ciliate. Scapes reach 24–30 cm, 2-angled, and bear setose-ciliate along angles, covered by leaf sheaths from 1/3 to 1/2. Spathe 1-valved, membranous, persistent; Umbel few flowered. Pedicels unequal, 3–5.5 cm, ebracteolate. Perianth purple red; segments with purple midvein, free at base; inner segments slightly longer and wider than outer ones, elliptic-oblong obtuse or rounded at apex, 4–6 × 1–1.3 mm; outer ones ovate or boat-shaped, apex retuse to obtuse or acuminate, 4–5 × 1–1.2 mm. Filaments unequal, outer filaments clearly longer than inner ones, outer filaments obviously broadened at base, with 1-toothed on each side at base, teeth 1–1.2 mm long, apex of tooth usually forming 1–2 irregularly obtuse or minute faint blunt denticules, rarely entire; inner filaments broadened at base ca. 0.3–0.5 mm wide, slightly narrower than outer ones, with 1 obtuse tooth on each side, teeth 0.3–0.6 mm long, entire at apex. Ovary obovoid-globose, with concave nectaries covered by hoodlike projections at base; ovules two per locule. Style exserted, 4–7 mm long; stigma entire. Capsule obovoid, 4–5 × 4–7 mm. Seed unknow.

Phenology: —Flowering and fruiting from August to September.

Etymology: —The specific epithet refers to the county name of the type locality. Hence, the Chinese name “ ffiffl ¨ (zhōu qū jiǔ)” is suggested.

Distribution and habitat: — Allium zhouquense is only known to its type locality, Zhouqu County in southern Gansu, China ( Fig. 4 ). It grows under a deciduous broadleaf forest or thicket with an elevational range 2800–3050 m, and exhibits adaptations to the habitat, with average temperature 11.8°C, and average annual precipitation ca. 960 mm.

Notes: — Allium zhouquense is found within the same valley as another species in the genus: A. plurifoliatum . These species typically inhabit shaded and moist habitats under mixed forests and share the same flowering time (August). Despite this proximity, no morphologically putative hybrids between them were observed during our study.

Figures

FIGURE 1. Habitat and habitus of Allium zhouquense. A–B Natural habitat under the mixed needleleaf and broadleaf forest from the type locality in Bailongjiang Chagangliang Provincial Nature Reserve of Zhouqu County, Gansu Province; C–E habitat and habit.

FIGURE 2. Morphology of Allium zhouquense. A Bulbs; B Leaves; C Leaf sheaths; D Spathes; E– F Inflorescence; G leaf, single flower and all parts of flower; H all parts of flower, ①outer filaments, ②inner filaments, ③outer tepals, ④inner tepals; I Capsule.

FIGURE 4. The distribution of Allium zhouquense in Gansu, China.