Phaseolus albescens McVaugh ex R. RamÍrez & A. Delgado (1999: 638)

Debouck, D. G., 2021, Phaseolus Beans (Leguminosae: Phaseoleae): A Checklist And Notes On Their Taxonomy And Ecology, Journal of the Botanical Research Institute of Texas 15 (1), pp. 73-111 : 77

Phaseolus albescens McVaugh ex R. RamÍrez & A. Delgado (1999: 638) [clade B; sect. Phaseoli DC. emend. Freytag ].

TYPE: A Delgado-Salinas et al. 1705 ( HOLOTYPE: MEXU n.v.; ISOTYPES: GH-423041 , K-651820 , NY-1104834 ).

It is a pluriannual vine in montane pine, fir, oak, ash forests on a few mountainous ridges of western Mexico ( RamÍrez-Delgadillo & Delgado-Salinas 1999) at 1300–2300 m. Apparently, it was Rogers McVaugh who first realized that this plant was not a P. coccineus nor a P. dumosus ( McVaugh 1987, p. 654) . Primary bracts and bracteoles are smaller as compared to those of P.dumosus , corolla pale lavender to old rose contrasting with purple in P.dumosus ( Fig. 2 ), and 4–5 seeds per pod (one less on average in wild P.dumosus ). It is possibly at risk because of the logging in these old-growth forests, namely in the area of El Fresnito (county of Zapotiltic in Jalisco) as noted by the author in November 2003.

Specimens: MEXICO. Jalisco: T Kajita 95120310 (MEXU-1235511). Colima: L Rico 926 (IBUG-133696). Michoacán: C Medina G. 3601 (IEB-148134). Guerrero: E Velázquez 479 (K).

Figures

FIG. 2. Close-ups of flowers of:a. P.albescens (R Lépiz 141), b.P.costaricensis (DG Debouck 2116), and c.P.dumosus (DG Debouck 1631).