Phaseolus viridis Piper (1926: 693) [clade B; sect. Paniculati Freytag].

TYPE: H von Tuerckheim II-897 (= John Donnell-Smith 8510) (HOLOTYPE: US-576636 n.v.; ISOTYPES: F-185839, GH-64113, O, US-942171).

This species seems to be valid, namely because of flower, pod (Fig. 10) and seed number traits, in spite of previous transfers into synonymy of P. lunatus (Delgado-Salinas 1985, Freytag & Debouck 2002). It is known by scattered populations across tropical Mexico and Guatemala and found in semi-evergreen seasonal forest at 10– 730 m. Studies with molecular markers on ITS/ 5.8S DNA and trnK cpDNA (Delgado-Salinas et al. 1999, 2006) have indicated a clear difference with P. lunatus . Phaseolus longiplacentifer Freytag would be a synonym of this species (Delgado-Salinas et al. 2006). Phaseolus longiplacentifer is reported in the list of “Vascular Plants of the Americas” (Tropicos 2020), while P.viridis is not.

Specimens: MEXICO. Veracruz: M Botteri 680 (P). Oaxaca: G Juárez-García 1086 (ARIZ-389122). Chiapas: E Palacios-Espinosa 1757 (CAS-852127).