Arisaema hui Z.X.Ma, Zi Rui Guo & R.K.Li, 2025

Ma, Zhengxu, 2025, Materia Revisionis Arisaemarum: III. taxonomic notes and five new taxa of the genus Arisaema (Araceae) from South China, Phytotaxa 697 (1), pp. 47-67 : 51-54

3.1. Arisaema hui Z.X.Ma, Zi Rui Guo & R.K.Li , sp. nov. ( Figs. 4 , 5 )

Arisaema hui differs from A. silvestrii in having an often non-reflected tuber, a caulescent pseudostem to 42 cm long, leaflets 13–15, all parts of inflorescence mottled with black dots, and a broadly auriculate spathe mouth with auricles to 0.8 cm wide.

Type: — CHINA. Chongqing Municipality: Qianjiang District, mountain valley west of road S209, near Houziyan, beside a stone path in deciduous forest, 8 March 2024, Y.E.Wang 162 (holotype BAZI!, isotypes BAZI!, E!, PE!).

Perennial geophyte, to ca. 80 cm tall, seasonally dormant, paradioecious. Subterranean stem tuberous, subglobose, erect, often not deflecting, to ca. 3.4 cm in diam., rarely bearing tubercles; accessory buds white with purple mottled, 2–4 grouped. Cataphylls 3, free. Foliage leaves 1–2; petiole and pseudostem glossily green mottled purplish brown, 22.3–67.5 long, petiolar sheath free, proximal ca. ½ sheathing into a caulescent and upright pseudostem; leaf blade pedate; leaflets 13–15, green, waxy, thickly membranous, oblanceolate, base sessile, broadly cuneate, apex acuminate; primary veins and lateral veins raised abaxially, concolor with petiole, laminae venation brochidodromous, forming a smooth collective vein near leaf edge; central leaflet 6.4–8.3 × 1.9–3.2 cm, largest or shorter than the adjacent leaflets; outermost leaflets often minute; rachis 12.4–25.6 cm long between central and outermost leaflets. Inflorescence solitary, below leaves when female, above when male, without obvious odor. Peduncle mottled purplish brown, glossy, always proportionally longer in male than female. Spathe tube abaxial surface green with very obscure dark green striation, with dark purple dots aligning vertically, white at base, slightly glaucous, adaxial surface nearly glossily green, cylindric to long funnelform, 4.3–9.5 cm long, 0.9–2.7 cm in diam. at the narrowest point; spathe mouth greenish, broadly auriculate, auricle 0.5–0.8 cm wide, sometimes recurving; spathe limb abaxially green, with black dots vertically aligning, adaxially glossily green, lanceolate to acuminate-ovate, bending forward and flat, 6.2–8.5 cm long. Spadix unisexual, 7.5–12.3 cm long; female zone cylindric, somehow pyramidoid, to 2.7–3.0 cm long, 0.4–1.2 cm in diam.; gynoecium densely arranged; ovary glossy green, obovoid, 1-locular; placentation basal; style very short; stigma white, puberulent; male zone cylindric, 1.4–1.7 cm long; androecium lax; synandrium consisting 2 bithecal anthers, cofiliment short; thecae dark purple, globose, dehiscing by a short slit resulting in an apical pore; appendix greenish yellow, with black dots, erect, slender claviform, to 4.1–9.3 cm long, 0.2–0.8 cm in diam., somewhat clavate to the apex, proximal part sessile, subulate neuters present in female, absent in male. Mature infructescence unknown. Anthesis from March to Early April.

Distribution: —S Chongqing (Qianjiang) and N Guizhou (Jiangkou), endemic to Central China.

Eponymy: —The species epithet “ hui ” honors Zheng-Kun Hu of the Administrative Bureau of Fanjingshan National Nature Reserve for his extensive exploration of the local flora and fauna of Mt. Fanjingshan. He was the first to encounter this new species in 2022.

Additional specimens examined (paratypes): — CHINA. Chongqing: Qianjiang, valley at west of road S209, near Houziyan , beside stone path, 8 March 2024, Y.E.Wang 154 (BAZI!, PE!) ; loc. ibid., 14 May 2024, R.K. Li s.n. (BAZI!). Guizhou: Jiangkou, Mt. Fanjingshan, at the entrance of Fanjing Mountain Scenic Area , in Bamboo forests behind the farmhouse, next to the boundary monument of the reserve, 10 March 2023, Zheng-Kun Hu s.n. (BAZI!) ; loc. ibid., 2 March 2024, Y.E. Wang 129 (BAZI!, PE!) ; loc. ibid., Mt. Fanjingshan, Yamugou Scenic Area , trailside next to the monkey statues, under the deciduous forest by the stream, 2 March 2024, Y.E.Wang 131 (BAZI!, PE!) .

Figures

FIGURE 4. Habit of Arisaema hui. A, B. Individuals from S Chongqing (type gathering), Y.E. Wang 162 (BAZI!); C, D. population from N Guizhou, Y.E.Wang 129 (BAZI!).

FIGURE 5. Inflorescence of Arisaema hui. A, B. Inflorescences in bunches showing the pattern of variation; C–E. inflorescence in different views, note the broadly auriculate spathe-mouth; F. female spadix; G. male spadix.A, C–G are individuals from the type gathering in S Chongqing, Y.E.Wang 162 (BAZI!), while B represents a population from N Guizhou, Y.E. Wang 129 (BAZI!).