| Distribution | Caatinga (Bahia, Brazil) | Abayoy (Santa Cruz, Bolivia) |
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| | glabrescent but with some lepidote scales | glabrous and without lepidote scales |
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| Branches | | tomentose in the terminal apices with dense stellate trichomes but these completely covered by a clear resinous secretion | terminal apices with dendroid trichomes, but without any resin |
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| Petiole | | glabrous but with some lepidote scales | glabrous, without lepidote scales |
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| | petiolule <0.5 cm long or subsessile | petiolules 1–2.5 (3) cm long |
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| Lateral leaflets | base symmetrical, usually cordate, sometimes rounded | base asymmetrical, usually obtuse or rounded, sometimes truncate |
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| | petiolules 0.4–2.2 cm long | petiolules (1.5) 2–3.5 cm long |
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| Terminal leaflets | base symmetrical, usually cordate, sometimes rounded | base symmetrical or slightly asymmetrical, usually obtuse or rounded, sometimes truncate |
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| Leaflets | | dark olive and with lepitote scales on the upper surface | glaucous or lustrous on the upper surface, without lepidote scales |
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| | pale olive and papillose on the lower surface | cinereous and not papillose on the lower surface |
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| Blades | margin not cartilaginous, serrate or irregularly dentate; almost spiny | margin cartilaginous, entire, repand, crenulate or slightly serrate (mainly at the apex) |
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| | no visible glands in the lower surface | with glands visible and dispersed on the lower surface |
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| Inflorescences | peduncle, pedicel, bracts and bracteoles puberulent or puberulous-mealy, with lepidote scales and stellate trichomes | peduncle, pedicel, bracts and bracteoles pulverulent, dendroid trichomes; lepidote scales absent |
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| Calyx | mealy pubescent only near base (stellate trichomes), the rest of the surface usually covered by a resinous secretion | completely pulverulent with dendroid trichomes, resin absent |
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| Flowers | Corolla tube | sparsely but distinctly puberulous outside with stellate trichomes, mostly glabrous inside | pilose or pubescent outside, glabrous or glabrescent inside (dendroid trichomes) |
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| Corolla lobes | sparsely puberulent or glabrescent on the outside, pubescent or tomentose on the inside | pilose or pubescent on both surfaces |
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| Ovary | c. 2.5–3 mm long | c. 3.5–4 mm long |
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