13. Apodanthera Arnott, J. Bot. (Hooker). 3: 274. 1841.
Melon loco [Greek a-, without, podos, foot, and anthera, anther, alluding to sessile anthers] Melon loco [Greek a-, without, podos, foot, and anthera, anther, alluding to sessile anthers]
Plants perennial, monoecious [dioecious], prostrate and trailing; stems <annual>, strigose; roots tuberous; tendrils unbranched or 2–3-branched. Leaves: blade reniform to orbiculate-cordate, unlobed or shallowly palmately 5-lobed [3–5-foliolate], lobes rounded, margins dentate, often undulate-crisped, surfaces eglandular. Inflorescences: staminate flowers (1–)2–5 in racemes [corymbs] from proximal axils; pistillate flowers 5–12 in fascicles in distal axils [solitary]; bracts filiform-subulate or absent. Flowers: hypanthium subcylindric to narrowly funnelform; sepals 5, linear-lanceolate; petals 5, distinct, yellow, oblong-obovate to elliptic-oblanceolate, [ovate or ovate-lanceolate], [1–]16–25(–35) mm, glabrate, corolla broadly funnelform-campanulate to rotate. Staminate flowers: stamens 3; filaments inserted near hypanthium rim, distinct, nearly vestigial; thecae distinct, oblong to suborbiculate, connective narrow; pistillodes absent. Pistillate flowers: ovary 3-locular, ovoid to oblong; ovules ca. 3–35 per locule; style 1, short-columnar to nearly absent; stigmas 3, linear; staminodes absent. Fruits pepos, silvery green to green with darker, raised, broad, longitudinal stripes, subglobose to depressed-globose [ovoid or ellipsoid], smooth or ribbed, indehiscent. Seeds [8–]30–80[–100], ellipsoid-obovoid [ovoid to obovoid or broadly ellipsoid], biconvex [compressed], not arillate, margins a broad, flat, light-colored band, surface smooth. x = 14.
Species ca. 19 (1 in the flora): sw United States, Mexico, Central America, South America.
Plants of Apodanthera were reported to be gender-diphasic, switching from staminate to pistillate (V. A. Delesalle 1989). Apodanthera herrerae Harms, a species of Andean South America, is grown for its edible tubers.