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Genus :


Family :



Erect or trailing, glabrous or villous herbs. Leaves opposite, crenate-serrate to dentate. Flowers solitary in leaf axils or in cymes or racemes. Calyx ribbed or winged, often 2-lipped and shortly toothed, usually 5-lobed. Corolla tube often dilated towards apex, limb bilabiate, lower lip 3-lobed, spreading, lobes subequal, upper lip erect, entire, emarginate or 2-lobed. Stamens 4, didynamous, anthers connivent in pairs. Ovary with short coarse hairs, stigmas bilamellate. Capsules oblong, included in persistent calyx, septicidal. Seeds numerous, scrobiculate.

Key to the species

Serial Key Reference
1a. Anterior filament each with a filiform or clavate spur slightly above base 2
1b. Anterior filament without spur 4
2a. Flowers small, less than 1.5 cm long; calyx keeled, not winged. Stem erect, not rooting at node, corolla yellow T. flava
2b. Flowers 2.5-3.5 cm long; calyx narrowly winged 3
3a. Stem sharply quadrangular; longer pair of filaments toothed; corolla lobes deep violet purple at apex T. diffusa
3b. Stem not sharply quadrangular; longer pair of filaments not toothwd; corolla lobe purple red to blue red T. asiatica
4a. Flowers solitary and axillary, or 2-4 in subumbels at nodes of branches; calyx oblong-ovoid to ovoid; wings decurrent to pedicels T. violacea
4b. Flowers in racemes at the ends of branches; calyx elliptic; wings not or shortly decurrent to pedicel T. fournieri