Davis Mountain Rocktrumpet

Macrosiphonia hypoleuca (Benth.) Muell.-Arg
Linnaea30:452. 1860.
Echites hypoleuca Benth. PI. Hartw. 23. 1839. a t^^ -, «. .
Echites suaveolens Mart. & Gal. Bull. Acad. Brux. lli; 356. 1844. Not E. suaveolens A. DC. 1844.
Macrosiphonia Wrightii A. Gray, Syn. Fl. N. Am. 2^: 83. 1878. Rhodocalyx suaveolens Miers, Apoc. S. Am. 139. 1878. Rhodocalyx hypoleucus Miers, Apoc. S. Am. 140. 1878.
Erect or diffuse suffrutescent herb, 1-3 dm. tall; leaves narrowly oblong to linear, 20-90 mm. long, 4-22 mm. broad, acute, or rarely acuminate or narrowly obtuse, abruptly rounded, obtuse, or truncate at the base, dark-green and hirtellous to glabrate above, much paler and densely tomentulose beneath, the petioles 1-2 mm. long; inflorescence bearing 1-3 white vespertine flowers, the peduncle conspicuous, somewhat shorter than the leaves; pedicels 5-10 mm. long; calyx-lobes narrowly oblong-lanceolate, acuminate, 5-10 mm. long, somewhat petaloid, minutely puberulent-tomentulose ; corolla infundibuliform, finely floccose-tomentulose externally, the tube proper 10-25 mm, long, about 1.25 mm. in diameter at the base, the throat narrowly conic or subtubular, 15-25 mm. long, 5-7.5 mm. in diameter at the orifice, the lobes obliquely obovate, 15-25 mm. long, spreading; follicles stout, continuous or slightiy articulate, 9-13 cm. long, finely puberulent-papillate.
Type locality: Aguascalientes, Aguascalientes. Distribution: Chihuahua to Guanajuato and Michoacan.

Mandevilla hypoleuca là một loài thực vật có hoa trong họ La bố ma. Loài này được (Benth.) Pichon mô tả khoa học đầu tiên năm 1948.