Key to Genera of Trichantherinae 1a. Calyx 3-lobed; corolla throat conspicuously gibbous-saccate ventrally; seeds 12–24 per capsule; pollen pantoforate............................................. Louteridium 1b. Calyx 5-lobed; corolla throat sometimes ampliate but not conspicuously gibbous-saccate ventrally; seeds up to10 per capsule; pollen loxodicolporate............................ 2 2a. Corolla subcylindric (or at least with the tube subcylindric and elongate; or if with a ± ampliate throat as sometimes in Suessenguthia multisetosa, then with flowers borne in headlike involucres subtended by several pairs of bracts); fertile stamens 2 or 4................. 3 2b. Corolla ± campanulate (i.e., throat ampliate; flowers not borne in headlike involucres as described above); fertile stamens 4............................................. 5 3a. Fertile stamens 2..................................................... Sanchezia 3b. Fertile stamens 4............................................................ 4 4a. Thecae awned at base.............................................. Suessenguthia 4b. Thecae awnless................................................. Trichosanchezia 5a. Thecae awnless, rounded at base; capsule pubescent at maturity; flowers borne on pedicels 2–11 mm long; stigma 1.5– 4.5 mm long............................... Trichanthera 5b. Thecae awned with a single, subulate projection 0.3– 1 mm long at base; capsule glabrous at maturity; flowers sessile or borne on pedicels to 2 mm long; stigma to 1 mm long. Bravaisia

Published as part of Daniel, Thomas F., 2015, Synopsis of Trichanthera (Acanthaceae: Ruellieae: Trichantherinae), pp. 1-23 in Proceedings of the California Academy of Sciences 62 (1) on page 2, DOI: 10.5281/zenodo.11066749