Gonolobus, Michaux, 1803

Lozada-Pérez, Lucio & Castro, Ericka Belén Cortez, 2023, A new species of Gonolobus (Apocynaceae) from Veracruz, Mexico, Phytotaxa 613 (1), pp. 69-74 : 73

Identification key for the species of Gonolobus in the Los Tuxtlas region, Veracruz

1. Dorsal appendages of the anthers entire, without forming 2 well-defined arms................................................................................2

- Dorsal appendages of the anthers slightly to deeply divided, forming 2 well-defined arms .............................................................4

2. Corolla lobes 4–4.5 mm long ................................................................................................................................................. G. niger

- Corolla lobes 26–35 mm long ............................................................................................................................................................3

3. Base of the leaf blade rounded, obtuse, acute to truncate, abaxially with long trichomes.......................................... G. sanmartinus

- Base of the leaf blade lobed, abaxially with mixed indumentum.................................................................................... G. versicolor

4. Faucal ring cup-shaped, slightly 5-lobed, up to 0.5 mm tall ............................................................................................ G. fraternus

- Faucal ring an erect tube, entire or inconspicuously 5-lobed........................................................................................... G. ancorifer