New taxonomic circumscription to Chamaecrista ser. Setosae (H. S. Irwin & Barneby) H. S. Irwin & Barneby (Leguminosae, Caesalpinioideae) Author Oliveira, Jaqueline Aparecida De 0000-0002-6191-8021 Universidade Federal de Goiás, Departamento de Botânica, CP 131, 740001 - 970, Goiânia, GO, Brasil & jaquelinebiooliveira @ gmail. com; https: // orcid. org / 0000 - 0002 - 6191 - 8021 jaquelinebiooliveira@gmail.com Author Mendes, Thainara Policarpo 0000-0002-5349-0045 Universidade Estadual Paulista ‘‘ Júlio de Mesquita Filho’ ’, Campus Botucatu, Departamento de Botânica, Instituto de Biociências, CP 510 ,, SP 18618 - 970, Brazil & thainara. bio. ufg @ gmail. com; https: // orcid. org / 0000 - 0002 - 5349 - 0045 thainara.bio.ufg@gmail.com Author Souza, Alessandro Oliveira De 0000-0002-6191-8021 jaquelinebiooliveira @ gmail. com; https: // orcid. org / 0000 - 0002 - 6191 - 8021 & alessandro 341 @ hotmail. com; https: // orcid. org / 0000 - 0002 - 7057 - 3942 jaquelinebiooliveira@gmail.com Author Silva, Marcos José Da 0000-0001-9717-5701 Universidade Federal de Goiás, Laboratório de Morfologia e Taxonomia Vegetal, Departamento de Botânica, Instituto de Ciências Biológicas, CP 131, Goiânia, GO 74001 - 970, Brazil & marcos _ agrorural @ hotmail. com; https: // orcid. org / 0000 - 0001 - 9717 - 5701 marcos_agrorural@hotmail.com text Phytotaxa 2021 2021-03-12 490 2 118 158 http://dx.doi.org/10.11646/phytotaxa.490.2.1 journal article 10.11646/phytotaxa.490.2.1 1179-3163 5753717 Key to species of Chamaecrista series Setosae 1. Leaves with 1 pair of leaflets..............................................................................................................................................................2 - Leaves with 2 or 3 pairs of leaflets.....................................................................................................................................................3 2. Subshrub 0.12–1 m tall; Leaves with petiole 1–4 cm long; leaflets oblanceolate or oboval-spatulate, surface adaxial scabroussetulose, base asymmetrically cuneate or attenuate; pedicel 1.7–3.6 cm long; flowers with 4 petals oboval and 1 asymmetrically oboval .............................................................................................................................................................................8. Ch . scabra - Shrub 1.5–2.5 m tall; leaves sessile; leaflets rhombic, elliptical or asymmetric-oval, adaxial surface setulose, base conspicuously asymmetric; pedicel 1–1.4 cm long; flowers with 5 petals similar oboval ............................................................1. Ch. auriszerdae 3. Leaflets heteromorphic, one pair reniform and other suborbicular; petiole up to 3 mm long ...................................... 5. Ch. obtecta - Leaflets isomorphic; petiole 1–9 cm long ..........................................................................................................................................4 4. Leaflets carthaceous or papyraceous ..................................................................................................................................................5 - Leaflets coriaceous .............................................................................................................................................................................6 5. Leaflets elliptical with flat margin; tertiary veins non-prominent on the abaxial surface; anthers conspicuously mucronate; seeds oblongoid; plants from the states of Goiás, Distrito Federal, Mato Grosso, Mato Grosso do Sul , and Minas Gerais ......................... ....................................................................................................................................................................................4. Ch. multiseta - Leaflets oblong, oblong-lanceolate or oval with margin revolute; tertiary veins prominent on the abaxial surface; anthers slightly mucronate; seeds pyriform; plants from Venezuela and Amazon region of Brazil ............................................... 7. Ch. orenocensis 6. Subshrubs or shrubs, 1–5 m tall; leaves with 2 or 3 pairs of leaflets; flowers in panicle ..................................................................7 - Shrubs 0.3–0.8 m tall; leaves always with 2 pairs of leaflets; flowers in typical racemes.................................................................8 7. Leaflets with secondary veins perpendicular in relation to the main and anastomosed in a submarginal vein; inflorescence puberulent, never setose or setulose ...........................................................................................................................3. Ch. coradinii - Leaflets with secondary veins ascending in relation to the main and anastomosed before the margin; inflorescence setose- or setulose-viscous...............................................................................................................................................................9. Ch. setosa 8. Plant decumbent and non-cespitose; leaflets and axes of inflorescence setose-stellate; flowers 3.4–4 cm long; legume setose ........ ..................................................................................................................................................................................2. Ch. campicola - Plants erect and caespitose; leaflets glabrous; axes of inflorescence setose or setulose; flowers 1–2 cm long; legume puberulent... ............................................................................................................................................................................. 6. Ch. ochrosperma