Phaseolus oligospermus Piper (1926: 698)

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 : 93

Phaseolus oligospermus Piper (1926: 698) [clade A; sect. Brevilegumeni Freytag]. TYPE: AS Oersted 30 (HOLOTYPE: K-478466; no isotypes seen so far nor mentioned in the original publication).

It is the reference species for the section. Sometimes confused with P.tuerckheimii ( Fig. 3 ), it is known by scattered populations from Mexico east of the Isthmus of Tehuantepec down to central Costa Rica in premontane moist mixed (oak, pine, alder, sweet gum) forest at 450–2100 m.

Specimens : MEXICO. Oaxaca: R Torres-Colin 10589 ( IBUG-169373 ). Chiapas: J Acosta-Gallegos 194 (K-1041773). HONDURAS. Francisco Morazán: JL Linares 6520 ( MO-6132749 ). EL SALVADOR. Ahuachapán: JL Linares 3303 ( LAGU). NICARAGUA. Estelí: CA Padilla-GÓmez 40 ( MO-6244283 ). Madríz: WD Stevens 16119 ( MO-5149147 ). COSTA RICA. San José: DG Debouck 3333 (USJ-111445) .

Figures

FIG. 3.Close-ups of flowers of:a.P.albicarminus (DG Debouck 3242),b.P.angucianae (DG Debouck 3243), c.P.hygrophilus (DG Debouck 3172),d. P.oligospermus (DG Debouck 3333), and e.P.tuerckheimii (DG Debouck 2134).