Chamaecrista series Setosae (H. S. Irwin & Barneby, 1978)

Oliveira, Jaqueline Aparecida De, Mendes, Thainara Policarpo, Souza, Alessandro Oliveira De & Silva, Marcos José Da, 2021, New taxonomic circumscription to Chamaecrista ser. Setosae (H. S. Irwin & Barneby) H. S. Irwin & Barneby (Leguminosae, Caesalpinioideae), Phytotaxa 490 (2), pp. 118-158 : 128

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