Description from
Flora of China
Cuscuta approximata var. urceolata (Kuntze) Yuncker; C. planiflora Tenore var. approximata (Babington) Engelmann; C. urceolata Kuntze.
Stems filiform, less than 1 mm in diam. Inflorescences lateral, compact glomerules, few to many flowered. Flowers sessile. Calyx cupular, 2-2.5 mm; sepals overlapping, broadly rhomboid, thickened abaxially. Corolla white to pink, campanulate, 2-2.5 mm; lobes triangular-ovate, shorter than tube. Stamens inserted at throat, shorter than corolla lobes; anthers ovate-circular, ca. as long as or shorter than filaments; scales oblong, not reaching base of filaments or ca. as long as corolla tube, apex obtuse or 2-cleft, fimbrillate. Ovary subglobose. Style ca. as long as or shorter than filiform stigmas. Capsule enclosed by withered corolla, subglobose, circumscissile. Seeds ovoid, ca. 1 mm. 2n = 14, 28.
According to Kamelin (in litt.), the specimens identified as Cuscuta approximata require further study. Possibly two or three species are combined in this description, one of them probably C. cupulata Engelmann. Cuscuta approximata is known to be strictly parasitic on Medicago.