Phaseolus sonorensis Standley (1940a: 31) [clade B; sect. Paniculati Freytag].

TYPE: HS Gentry 1396 (HOLOTYPE: F-770502; ISOTYPES: BM, DES, GH-64109, K, MICH-1104264, MO-1089160, UC-646354, WIS-3983).

A tall plant growing in pine-oak forest at 1100–1800 m with large showy magenta flowers. It blooms in spring as often does P. salicifolius and P.albinervus too. Pending additional field work, it is still considered as endemic (an opinion shared by Fishbein et al. 1998), but it might have a larger range in the Sierra Madre Occidental.

Specimens: MEXICO. Chihuahua: R Spellenberg 8081 (NMC-14198). Sinaloa: RA González 236 (MEXU-800335). Sonora: M Fishbein 1015 (ARIZ-304231).