Cuscuta mitriformis
Diagn. Pl. Nov. Mexic. 3: 54. 1880. (as mitraeformis)
Stems orange, medium to coarse. Inflorescences dense, corymbiform-glomerulate; bracts at base of clusters 1, at base of pedicels 0(or 1), ovate-triangular, fleshy to membranous, margins entire, apex acute. Pedicels 0.5–2 mm. Flowers 5-merous, 4–5.5 mm, receptacle and calyx fleshy, corolla membranous, not papillate; calyx brownish, shallowly cupulate, equaling corolla tube length, divided 1/3 its length, ± reticulate and shiny, lobes broadly ovate, bases overlapping, margins entire, midvein ± carinate, apex obtuse, sometimes with an appendage; corolla white, drying creamy brown, 3.6–5 mm, tube campanulate, 1.5–3.5 mm, not saccate, lobes spreading to reflexed, broadly ovate, equaling corolla tube length, without hornlike appendages, margins entire, apex obtuse, straight; infrastaminal scales ovate to oblong, 1.5–3.5 mm, equaling corolla tube length, bridged at 0.4–0.7 mm, truncate to rounded, sparsely fimbriate (sometimes only distally), fimbriae 0.1–0.4 mm; stamens slightly exserted, shorter than corolla lobes; filaments subulate, 0.5–0.9 mm; anthers 0.5–0.9 × 0.3–0.4 mm; styles stout, subulate, 0.9–2 mm, shorter than ovary. Capsules globose, 4–7 × 4–6 mm, thickened and raised around relatively large interstylar aperture, not translucent, surrounded by withered corolla at base, dehiscence circumscissile. Seeds 4, angled, subglobose to broadly ellipsoid or ovoid, 1.9–2.3 × 1.9–2.3 mm, hilum region lateral.
Phenology: Flowering Jul–Sep.
Habitat: Hosts: Ageratina, Ambrosia, Bouvardia, Commelina, Desmodium, Drymaria, Encelia, Eupatorium, Lupinus, Phaseolus, Salvia, Solanum, Stevia, Thalictrum, Verbena, and others.
Elevation: 1500–2500 m.
Discussion
Cuscuta mitriformis is relatively widespread in Mexico (Chihuahua, Coahuila, Durango, Estado de México, Guanajuato, Hidalgo, Michoacán, Nayarit, Nuevo León, Querétaro, Puebla, San Luis Potosí, Veracruz, and Zacatecas) but of conservation concern in the flora area, where it is known only from the Chiricahua Mountains in Cochise County, Arizona (M. Costea et al. 2013).
Selected References
None.