Key to species of Heterostemma sect. Oianthus in India 1. Corolla discoid or depressed globose or vertically compressed globose ......................... 2 1. Corolla urceolate or tubular ............................ 4 2. Corona lobes with inner appendages ................ ...................................................... H. vasudevanii 2. Corona lobes without inner appendages........ 3 3. Leaves ovate or broadly or narrowly ovate-lanceolate or ovate-cordate; corolla hairy inside................................................ H. beddomei 3. Leaves elliptic-oblong to ovate-oblong; corolla glabrous ........................................ H. disciflorum 4. Corolla tubular or rarely ovoid-urceolate; corona lobes rounded at apex........ H. deccanense 4. Corolla perfectly urceolate; corona lobes 3-toothed at apex......................... H. urceolatum

Published as part of K., Prasad & Abstract, B. Sadasivaiah, 2023, Rediscovery of Heterostemma beddomei (Apocynaceae, Asclepiadoideae) after its type collection in India over more than 150 years ago, pp. 17-21 in Rheedea 33 (1) on pages 20-21, DOI: 10.22244/rheedea.2023.33.01.03, http://zenodo.org/record/16897084