Key to the species and varieties of Agarista in Rio Grande do Sul state, Brazil

1. Petioles 6.26–15.81 (–21.43) mm long, thinner, flexuous and slender ........................................................... Agarista eucalyptoides

- Petioles 0.97–6.7 mm long, thicker, straight, and rigid......................................................................................................................2

2. Leaf blade orbicular, surface glabrous or with few glandular-headed trichomes.............................................. Agarista nummularia

- Leaf blade ovate, lanceolate, ellipitic, or oblong, surface with or without glandular-headed trichomes...........................................3

3. Leaf base cordate, margin strongly revolute, surface with densely glandular-headed trichomes ....................... Agarista chlorantha

- Leaf base rounded to truncate or cuneate, margin slightly revolute, surface without glandular-headed trichomes ..........................4

4. Leaf blade lanceolate to oblong; capsule placenta central to subapical; seeds trapezoid ....................................... Agarista minensis

- Leaf blade ovate to elliptic, rarely oblong; capsule placenta apical; seeds concave-convex .............................................................5

5. Leaf apex obtuse to retuse, blade 1–2.66 × 0.43–0.89 cm ....................................................... Agarista niederleinii var. niederleinii

- Lead apex acuminate to acute, blade 1.7–4.26 × 0.55–1.67 cm ............................................................. A. niederleinii var. acutifolia