桂平蘑芋 gui ping mo yu

Amorphophallus arnautovii Hetterscheid; A. pingbianensis H. Li & C. L. Long.

Tuber persistent, dark brown to blackish, depressed globose, to 3 cm high, to 6 cm in diam., chained with others to form a pseudorhizome of 2-6 modules, each 3-5 cm in diam. Leaves 1-3, lasting up to 3 years; petiole uniformly dark green, terete, 60-120 × 1-2 cm, turgid, glabrous; leaf blade to ca. 100 cm in diam.; rachises only winged distally, common base of 3 main branches sometimes developing into an intercalary bulbil; leaflets dark green, oblanceolate, 15-20 × 4-6 cm, acuminate. Inflorescence long pedunculate; peduncle colored as petiole, 10-50 × 0.6-1.3 cm. Spathe shortly convolute at base, outside green, dirty green flushed with dirty brownish purple or distal half entirely brownish purple; inside uniformly green or background color dirty green, at base and along midrib flushed dirty dark purplish, near apex less so, or base pale green and rest flushed with brownish purple, narrowly triangular to triangular-ovate, 7.5-15 × 3-7 cm, base within glabrous or nearly glabrous with a few scattered, small, punctiform warts, apex acute. Spadix giving off a heavy gaseous stench at female anthesis, sessile, pale yellowish green with a very faint greenish flush, as long as or longer than spathe, 10-19.5 cm; female zone cylindric, 1-2 × 1-1.6 cm, flowers congested; ovary green or pale whitish green, strongly depressed, depressed globose, or subglobose, 1.5-2 mm high, 1.5-4 mm in diam., angulate or irregularly orbicular in cross section, 1- or 2-loculed; style straight or slightly upcurved, pale green, 1-2 × ca. 0.8 mm; stigma pale yellowish or pale greenish, flattened, disciform or nearly so, 0.7-0.8 mm high, 0.8-2 mm in diam., irregularly orbicular or elliptic in cross section, entire with a shallow, elongate, central depression or shallowly 2-lobed, or more distinctly bilabiate, margin with 2 small notches or a few small lobes, densely verruculose or echinulate; male zone cylindric, apex slightly widened, terete or slightly compressed, 2.3-4.5 × 0.7-1.5 cm, flowers congested; male flowers consisting of 3 or 5 stamens; stamens ca. 2 × 1-2 mm; filaments ca. 0.7 mm, connate or largely free; anthers off-white, ca. 1.3 mm, truncate; pores apical, elongate and connected to margin of anther by a groove; appendix narrowly fusiform-conic, 5.5-14.5 cm, base 0.7-2.3 cm in diam., sometimes slightly compressed, glabrous or shallowly corrugate, base glabrous or with some flattened staminodes, separated by grooves, base constricted, apex acute. Fruiting zone at least 5 × ca. 4 cm. Berries dark blue, oval or oval-ellipsoid, ca. 1 × 0.8 cm, 1- or 2(or 3)-seeded. Fl. Mar.

Moist forested valleys, along water, thickets; 300-900 m. Guangxi (Guiping, Rongshui), Yunnan [E and N Vietnam].

The inclusion of Amorphophallus arnautovii and A. pingbianensis in the synonymy of A. coaetaneus has been published and discussed by Hetterscheid and van der Ham (Blumea 46: 279-281. 2001).

In the protologue of Amorphophallus coaetaneus, the specific epithet was given in error as "guipingensis" in the figure caption on p. 186.