Lychnocephalus, Mart. ex Candolle, 1836

Gomes, Francisca Maiara Batista & Loeuille, Benoit, 2022, Taxonomic revision of Lychnocephalus (Lychnophorinae, Vernonieae, Asteraceae), an endemic genus of the Espinhaço Range, Minas Gerais, Brazil, Phytotaxa 547 (2), pp. 119-146 : 124

Diagnostic key for species of Lychnocephalus (modified from Gomes & Loeuille 2021)

1. Leaf blade narrow oblong; pappus usually uniseriate, if biseriate then outer series vestigial ...........................................................2

- Leaf blade elliptic, lanceolate, linear, obovate or wide oblong; pappus biseriate, outer series not vestigial .....................................3

2. Decumbent subshrubs; inflorescence sessile, 10–15 florets per capitulum ................................................................... L. humillimus

- Erect shrubs; inflorescence pedunculate, 6–8 florets per capitulum ................................................................................. L. grazielae

3. Leaf petiolate, venation eucamptodromous; corolla lobes pubescent ................................................................................................4

- Leaf sessile, mixed venation pattern parallelodromous-cladodromous; corolla lobes glabrescent....................................................5

4. Robust branch ((0.6–) 1–2.3 cm in diameter); third-order syncephalium spherical; 12–15 florets per capitulum; outer pappus not strongly reduced (longer than 1 mm) ............................................................................................................................ L. tomentosus

- Delicate branch (0.3–0.5 cm in diameter); third-order syncephalium hemispherical; 4–6 florets per capitulum; outer pappus strongly reduced (shorter than 0.5 mm) ..................................................................................................................... L. mellobarretoi

5. Shrubs or treelets moderately branched, stem densely lanulose; phyllary apex obtuse or rounded ................................. L. cipoensis

- Treelets poorly branched, stem densely lanate; phyllary apex acute (rarely obtuse) .........................................................................6

6. Secondary veins of the abaxial surface concealed by indumentum; corolla shorter than 1.8 cm ........................................ L. sellovii

- Secondary veins of the abaxial surface not concealed by indumentum; corolla longer than 1.8 cm .................................................7

7. Leaf blade wide lanceolate to oblong, apex acute; indumentum of leaves, bracts and syncephalia whitish; involucre cylindrical, 4–7 florets per capitulum........................................................................................................................................................... L. jolyanus

- Leaf blade narrow lanceolate, apex attenuate; indumentum of leaves, bracts and syncephalia greyish-white; involucre campanulate, 10–15 florets per capitulum.................................................................................................................................................... L. canus