Severinia buxifolia (Poir.) Tenore, Ind. Sem. Hort. Neap. 3. 1840; Swingle, Citrus Ind. 1: 284. 1967. Citrus buxifolia Poir. in Lam., Encycl. Meth. 4: 580. 1797. Limonia bilocularis Roxb., Fl. Ind. ed. 2: 377. 1832; Hook. f., Fl. Brit. India 1: 508. 1875. Sclerostylis atalantioides Wight & Arn., Prodr. 93. 1834, non Wight 1840. Severinia monophylla (L.) Tanaka in J. Bot. 63: 232. 1930.

Shrubs up to 1.5 m high; branches strong, rigid, armed with sharp, straight, solitary spine in leaf axils; bark green or grey, lenticellate. Leaves shortly petiolate, ovate-elliptic, narrow or rounded at base, obtuse and emarginate at apex, crenulate along margins, 2 - 4 x 1 - 2 cm, thick, rigid, dark green, profusely gland dotted, glabrous; secondary nerves many, parallel, very distinct and finely reticulate. Flowers usually in 2- or 3-nate fascicles. Calyx campanulate, 5-lobed; lobes rounded, obtuse. Petals 5, erect, oblong, obtuse, ca 4 x 1.5 mm, glandular, glabrous, imbricate, white. Stamens 10; filaments linear-subulate, 2 - 3 mm long; anthers ovoid. Ovary sessile, deeply sunken in a cupular, fleshy, greenish-white disk, subglobose, glabrous, 2- or 3-locular with 1 ovule in each locule; style short; stigma capitate, 2- or 3-lobed. Berries globose, depressed above, flesh y, glandular, purplish or turning blackish when ripe; seeds ovoid, large, 2 or 3, rarely one.

This species is known only under cultivation in India. It is indigenous in S. China, N. Vietnam, S. Vietnam, Thailand, Hongkong, Cambodia and Laos.

It has been used as a successful rootstock for Citrus. Chinese use the leaves for preparing yeast cakes.

This species, like Citrus limon, is tolerant to boron and hence could probably be considered as an ecological indicator.