Phaseolus campanulatus Freytag & Debouck (2002: 224) [clade A; sect. Brevilegumeni Freytag].

TYPE: R McVaugh 16341 (HOLOTYPE: MICH-1210016).

This species known by only a few collections from western Mexico is close to P. oligospermus, but with differences such as leaf shape and number of seeds (five) per pod (Lépiz-Ildefonso & RamÍrez-Delgadillo 2010). It grows in mixed broadleaf oak forest at 1300–1400 m.

Specimens: MEXICO. Jalisco: JA Solís-Magallanes 1961 (MEXU-330005). Nayarit: O Téllez-Valdés 9346 (IBUG-169372).