Compact dodder

Cuscuta compacta var. efimbriata Yuncker

Stems yellow-orange, coarse. Inflorescences dense to loose, glomerulate, often originating endogenously; bracts at base of clusters, pedicels, and/or flow­ers 2–4(–6), ovate-orbiculate, fleshy, margins scarious, finely denticulate-fimbriate, apex erect, obtuse. Pedicels 0–1 mm. Flowers 5-merous, 4–6 mm, fleshy, not papil­late; calyx brown-yellow, cylindro-campanulate, 3/4 corolla tube length, divided to base or nearly so, finely reticulate, shiny, lobes orbiculate, bases broadly overlapping, margins scarious, minutely denticulate-fimbriate, midvein not carinate, apex rounded; corolla white to creamy greenish, drying creamy brown, 3.8–4.5 mm, tube cylindric, 3–4 mm, not saccate, lobes spreading to reflexed, ovate, 1/3–1/4 corolla tube length, margins entire, apex obtuse, straight; infrastaminal scales oblong to obovate, 2.6–3.3 mm, 3/4 to equaling corolla tube length, bridged at 0.9–1.3 mm, usually densely fimbriate in distal 1/2–3/4, sometimes reduced, 2-fid with 1–3 fimbriae on each side of filament insertion or dentate-winged, fimbriae 0.4–0.8 mm; stamens exserted, shorter than corolla lobes; filaments 0.2–0.3 mm; anthers 0.3–0.4 × 0.3–0.4 mm; styles filiform, 1–2 mm, longer than ovary. Capsules conic-globose to broadly ellipsoid, 3–5(–6) × 2–2.5 mm, thickened and slightly umbonate around relatively small interstylar aperture, not translucent, capped by withered corolla, indehiscent. Seeds 1–4, obcompressed, broadly ovoid to broadly ellipsoid, 1.9–2.5 × 1.7–2.3 mm, hilum region subterminal. 2n = 30.

Flowering late Jul–Nov. Hosts: Acer, Alnus, Ampel­opsis, Baccharis, Campsis, Carpinus, Carya, Cephalan­thus, Cissus, Clethra, Cornus, Cyrilla, Deco­don, Eupa­torium, Hydrangea, Ilex, Iva, Lespedeza, Leucothoë, Lindera, Ludwigia, Magnolia, Myrica, Parthenocissus, Rhus, Rosa, Rubus, Sambucus, Sassafras, Smilax, Tecoma, Vaccinium, Viburnum, Vitis, and other herbs and woody plants; wetland margins, wet woodlands; 30–300 m; Ala., Ark., Conn., Del., D.C., Fla., Ga., Ill., Ind., Iowa, Ky., La., Md., Mass., Miss., Mo., N.H., N.J., N.Y., N.C., Okla., Pa., R.I., S.C., Tenn., Tex., Va.

Cuscuta compacta var. efimbriata was treated as a synonym of C. compacta by D. F. Austin (1980). Yuncker recognized its presence in Florida (the type collection) and Arkansas; these plants apparently are populational variants, distinguished by infrastaminal scales shorter than the corolla tube, much reduced in size, bifid or winged, and reduced in marginal fimbriae.