Large-flowered flat-globe dodder

Stems yellow-orange, slender. Inflorescences dense to loose, umbelliform; bracts at base of clusters 1, at base of pedicels 0 or 1, broadly triangular-ovate, membranous, finely reticulate, slightly shiny, margins entire, apex acuminate. Pedicels 2–10 mm. Flowers 5-merous, 4–5.5(–6) mm, membranous, not papillate; calyx straw yellow, campanulate, 2.5–3.2 mm, longer than corolla tube length, divided 2/3 its length, finely reticulate, slightly shiny, lobes ovate-lanceolate, bases not over­lapping, margins entire, midvein not carinate, without multi­cellular protuberances, apex acuminate; corolla white, drying creamy white, 3.8–5.2(–5.6) mm, tube campanulate, 1.6–2.1 mm, not saccate, lobes reflexed, linear-lanceolate, longer than corolla tube length, margins entire, apex acuminate, straight; infrastaminal scales spatulate to obovate, 1.8–2.2 mm, equaling or slightly longer than corolla tube length, bridged at 0.2–0.4 mm, rounded, uniformly densely fimbriate, fimbriae 0.2–0.5 mm; stamens exserted, shorter than corolla lobes; filaments 0.6–1 mm; anthers 0.5–0.7 × 0.2–0.3 mm; styles filiform, 0.9–2.5 mm, longer than ovary. Capsules depressed-globose, 2–3 × 1–2 mm, irregularly thickened and slightly raised around inconspicuous interstylar aperture, translucent, surrounded or capped by withered corolla, dehiscence circumscissile. Seeds 2–4, broadly ellipsoid to subglobose, 0.9–1.2 × 0.8–0.9 mm, hilum subterminal.

Flowering Aug–Nov. Hosts: Allionia, Amaranthus, Boerhavia, Chamaesaracha, Evolvulus, Kallstroemia, Salsola, Solanum, Tidestromia, Trianthema, Tribulus; 40–1200 m; Ariz., N.Mex., Tex.; Mexico (Baja California, Chihuahua, Coahuila, Sonora, Tamaulipas).

Cuscuta legitima is a hybrid species closely allied with C. umbellata, from which it differs in larger flowers and acuminate calyx lobes.