Himatanthus

Amasifuen Guerra, Carlos A., Delprete, Piero G. & Spina, Andrea P., 2016, Synopsis of Himatanthus (Apocynaceae, Rauvolfiodieae: Plumerieae) species from Peru, Phytotaxa 283 (1), pp. 65-73 : 68

Key to the species of Himatanthus occurring in Peru

1 Leaf venation brochidodromous-eucamptodromus; secondary veins at 80–90° angle with the midrib ...................... 2. H. revolutus

1 Leaf venation brochidodromous; secondary veins at 50–80° angle with the midrib............................................................................2

2 Secondary veins at 50–70° angle with the midrib; corolla tube 15–20 mm long, lobes 20–25 mm long; style head glabrous; follicles 27–29 cm long................................................................................................................................................................3. H. tarapotensis

2 Secondary veins at 70–80° angle with the midrib; corolla tube 20–35 mm long, lobes 25–35 mm long; style head pubescent; follicles 16–26 cm long ..................................................................................................................................... 1. H. phagedaenicus