Craterostigma, Hochstetter, 1841

Liang, Yi-Shuo & Wang, Jenn-Che, 2016, New combinations in Craterostigma and Torenia (Linderniaceae) from Asia with key to allied species, Phytotaxa 247 (2), pp. 148-150 : 149

Key to the Asian species of Craterostigma

1 Annual herb, hygrophytic, caulescent; leaves opposite, on elongated stem ......................................................................................2

- Perennial herb, xerophytic, acaulescent; leaves opposite, rosulate, on congested stem ....................................................................3

2 Plant erect; stem glabrous; flowers in raceme or solitary-axillary, both pedicellate and sessile; corolla ventral central lobe pink to purple, dorsal lip purplish................................................................................................................................... C. nummulariifolium

- Plant creeping; stem pubescent; flower solitary-axillary, sessile; corolla ventral central lobe white to pale purple, dorsal lip pale brown........................................................................................................................................................................... C. sessiliflorum

3 Inflorescence racemose, peduncle elongate, much longer than short pedicels ......................................................... C. plantagineum

- Inflorescence single-flowered, peduncle much shorter than elongate pedicel .................................................................. C. pumilum