Asarum wannanense Lu Q. Huang & H. S. Peng, 2023

Peng, Hua-Sheng, Yin, Min-Zhen, Wang, De-Qun, Liu, Hao, Liu, He-Ling & Huang, Lu-Qi, 2023, Asarum wannanense, a new species of Aristolochiaceae from Southern Anhui, Eastern China, Phytotaxa 595 (1), pp. 115-119 : 116-118

Asarum wannanense Lu Q. Huang & H. S. Peng , sp. nov. ( Figs. 1 , 2 )

Diagnosis:—Similar to A. magnificum , though notable for calyx tubes constricted at middle and upper part with an orifice ca. 4 mm wide ring, which the orifice ring and the floral opening have been elongated into a secondary calyx tube with transversely corrugate characteristics.

Type:— CHINA. Anhui Province, Qimen County, Likou Town , under the evergreen broad-leaved forest, elev. 300–700 m, 2 May 2021, Peng HS 2021050201 (holotype ACM!; isotype ACM!) .

Herbs perennial. Rhizomes short and vertical, 1–3 mm in diam. Leaves solitary, nearly leathery; petiole 8–17 cm, pubescent; leaf blade adaxially deep green with or without white blotches, triangular-ovate or nearly triangular to elliptic-ovate, 7–13 cm long, 5–12 cm wide, apex acute, base auriculate-cordate, lateral lobes divaricate, 3–8 cm long, 3–8 cm wide, adaxial surface pubescent along midvein, abaxial surface green and glabrous, reticulate veins apparent; cataphylls ovate, ca. 2 cm long, ca. 1 cm wide, margin dense ciliolate. Peduncle recurved, 0.5–4 cm long. Calyx purplish green; calyx tube campanulate or long cylindric, 4.5–5 cm long, 1.2–2 cm in diam., the distal part of calyx tube abruptly swollen, then constricted at middle and upper part, with an orifice ring ca. 4 mm wide; the orifice ring and the floral opening have been elongated into a secondary calyx tube, transversely corrugate, orifice ring below the base of the tube longitudinally corrugate; lobes triangular-ovate, ca. 3 cm long, ca. 2 cm wide, base with triangular papillate area. Stamens 12. Filaments much shorter than anthers; connectives slightly extended beyond anthers, acute. Styles 6, free, apex 2-forked; stigmas lateral. Ovary half-inferior. Fruit and seeds not observed.

Distribution and habitat: — Asarum wannanense was found in the south of Anhui Province and its adjacent areas, southeast China. It grows on forests, thickets, mountain slopes, moist shady areas at elevations of 300– 700 m.

Phenology: —Flowering from March to June, fruits not observed.

Additional specimens examined (paratype): — CHINA. Anhui Province: Shitai County, Guniujiang National Nature Reserve, 273 m, 10 June 2018, Ningyu Xiong et al. NAS00611659 , NAS00611661 ( NAS!) .

Etymology: —The specific epithet “wannanense” refers to its distribution area of the southern Anhui and adjacent regions.

Vernacular name: —The Chinese name is “Wǎn Nán Xì Xīn” (Êfflâƚ).

Figures

FIGURE 1. Asarum wannanense Lu Q. Huang & H. S. Peng, sp. nov.A –A: habitat; B: front view of flower; C: side view of flower; D: 1 3 longitudinally dissected flower; E: longitudinally dissected ovary; F: dissected flower, showing the position of stamens and gynoecium; G: orifice ring.

FIGURE 2. Asarum wannanense Lu Q. Huang & H. S. Peng, sp. nov. A: flowering plant; B: longitudinally dissected flower; C: longitudinally dissected ovary; D 1: apical view of orifice ring; D 2: longitudinally dissected orifice ring; E: stamens and stigmas; F: stamen; H: style and stigma.