Amorphophallus cidarioides J.R.C.Callado, Medecilo & Hett., 2020

Hetterscheid, W. L. A., Medecilo, M. P., Callado, J. R. C. & Galloway, A., 2020, New species of Amorphophallus (Araceae) in the Philippines and an updated key, Blumea 65 (1), pp. 1-9 : 3-4

2. Amorphophallus cidarioides J.R.C.Callado, Medecilo & Hett. , sp. nov. — Plate 2

Etymology. The species epithet is based on the resemblance of the stigma with its extensions to species of the sea urchin genus Cidaris Leske.

Type. J.R.C. Callado JRCC 2516 (holo PNH 256729 ), Philippines, Panay Island, Luho , Brgy. Caratagan , Calinog , Iloilo , 22 Feb. 2017 .

Tuber depressed globose, 5–9 cm diam, 3.5–5.5 cm high. Petiole 88–132 cm long, 1.3–4 cm diam at the base, 0.9–2 cm at the top, surface smooth, whitish to very pale green with numerous, densely set, often confluent, narrowly elliptical dark brown spots and dots. Lamina 128–185 cm diam, rachises unwinged but for the most distal parts, developing swellings at the branching point, these verrucose and possibly forming new plants after leaf senescence; leaflets ovate to elongate elliptical, 17–32 cm long, 5.5–9 cm wide, long acuminate, upper surface dull dark green, collective vein rather distant from the margin, conspicuous. Inflorescence solitary; peduncle c. 70 cm long, 1.8 cm diam at the base, smooth, dirty pale brownish whitish with numerous narrowly elliptical, dark brown spots. Spathe triangular-ovate, 23 cm long, 10 cm wide, erect, base and limb not strongly separated, top involute and spiralling over a short distance, apex broadly acute, base inside verrucose, white, outside pale purplish with scattered, small, blackish green spots, limb inside maroon, outside purplish with numerous, scattered, small blackish green spots. Spadix sessile, shorter than spathe, 15.5 cm long; female zone cylindric, 3.5 cm long, 2.4 cm diam, pistils crowded; male zone cylindric, 4 cm long, 3.4 cm diam, stamens crowded; appendix fusiform-conical, 8 cm long, 3.5 cm diam above the base, base constricted forming a very short, stipe-like part of 2.4 cm diam, surface smooth, dark maroon, top obtuse. Ovaries depressed-globose, 2.5–3 mm diam, 2 mm long, angulate, off-white, unilocular; stigma sessile, depressed, triangular, 1–1.2 mm diam, 0.5 mm high, with three rod-like extensions, almost perpendicular to the stigma surface or more horizontally radiating from the centre; extensions cylindric, fleshy, 1.5 mm long, 0.2 mm diam, obtuse, base sometimes slightly thickened, surface rugulose, off-white. Number of stamens per male flower not determinable; stamens 3–3.5 mm long, narrowly cylindric, white; filaments free, 2 mm long, 0.5 mm diam; anthers 1–1.5 mm long, 0.8 mm diam; connective dome-shaped; pores subapical, slit-like.

Distribution — Only known from the type locality.

Note — A species unique in the entire genus because of the rod-like extensions on the stigmas. The thin, elongate stamens are also rare in the genus.

Figures

Plate 2 Amorphophallus cidarioides J.R.C.Callado, Medecilo & Hett. (type plant before conservation). a. Leaf lamina; b. inflorescence; c. lower part of spadix with female and male zone; d. detail of the female zone showing stigmas with rod-shaped extensions. — Photos by: M.P. Medecilo.