Ariopsis protanthera N.E.Br.

Very small, slender, seasonally dormant, lithophytic herbs with milky latex, to 12 cm tall. Stem a ± subglobose tuber, ca 2 cm diam., mostly clustered, covered with fibrous cataphyll remains. Leaves solitary; petiole very slender, 6–14 cm, sheath very short; leaf blade peltate, cordate-ovate, 5–10 × 4–10 cm, membranaceous, pale green above, glaucous below, posterior lobes short, fully fused; primary lateral veins pinnate, radiating from petiole insertion, forming submarginal collective vein; higher order venation reticulate. Inflorescences 1–3 in each floral sympodium, appearing before the leaves; peduncle very slender, 4–5 cm, much longer than spathe, erect to spreading; spathe ovate, boat-shaped, 2–2.5 × 1 cm, not constricted, hooded, gaping widely at anthesis, not convolute at base, marcescent, dull yellow; spadix shorter than spathe, ca 1.5 × 0.4 cm; pistillate flower zone adnate to spathe, ca 4 mm long, few-flowered; ovaries rhombic-ovoid to rhombic-ovoid-oblong, ca 3 × 4 mm, pale green speckled purple, stylar region very short, stigma stellate with 4–6 lobes, lobes initially erect, later spreading and reflexed, whitish green; sterile interstice free, naked, ca 3 mm long; staminate flower zone fertile to apex, cylindrical-conoid, ca 10 × 4 mm, many-flowered, dirty very pale yellow; synandria peltate, the connate filaments forming a stipe longer and narrower than dilated common connective, synandria all connate apically, forming continuous surface punctured by cavities with somewhat prominent margins into which pollen is shed from the 6(–8) surrounding thecae of which each pair of thecae belongs to a different synandrium; fruit a 4–6–angled berry, ca 5 × 5 mm, pale green, stigma persistent.