16. Chelonopsis Miquel in Ann. Mus. Bot. Lugd. Batavi. 2: 111. 1865. Benth. & Hook. f., Gen. Pl. 2: 1204. 1873; Briquet in Engler & Prantl, Nat. Pflanzenfam. ed. 1, 4, 3A: 243. 1896; Mukerjee in Journ. Ind. Bot. Soc. 21: 313-317. 1942.
Herbs or shrubs with a sparse indumentum of simple eglandular hairs. Stems erect, little branched, leafy. Leaves large, ovate to oblong-elliptic, finely crenulate or dentate, shortly petiolate, ternate or opposite. Flowers white, pink or purple, few, in cymes borne in axils of upper leaves, pedicellate. Bracts linear, shorter than calyces. Calyces triangular-campanulate, not bilabiate or scarcely so; teeth 5, triangular, ± as long as tube, equal or subequal; tube glabrous within; fruiting calyces somewhat enlarged. Corolla clearly exserted from corolla; upper lip ± straight, bifid; lower lip 3-lobed, median largest; tube broad gradually widened from base to throat, slightly curved, exannulate within. Stamens 4, didynamous, anterior pair longer, included within corolla upper lip; thecae bilocular, spreading, markedly bearded. Style ± equally bifid. Nutlets oblong-ellipsoid, apically winged or with a short flange.
About 16 species mostly in China; also in Japan and E. Tibet. A natural well-defined genus of uncertain affinity.