Premna herbacea Roxb.

A rare plant, of hard soil, in our area. It is said that the plant often comes up after forest fire.

A dwarf or small undershrub, almost stemless, forming a sort of underground, nodose runner from which annual flowering stems, 2-10 cm high, develop. Leaves obovate, 3-5(-8) cm long, 1.5-3 (-6) cm broad, coarsely serrate-dentate, sessile, usually villous beneath, puberulous above on the nerves, drying blackish, in 2-3 close pairs forming a rosette. Cymes terminal, trichotomous, not exceeding the leaves, dense, 2.5-4 cm across, villous. Flowers c. 2.5 mm across, pale yellowish or greenish. Calyx 2-2.5 mm long, cup-shaped, subequally and obtusely 5-toothed, pubescent. Corolla-tube 2.5-3 mm long; hairy in the throat; limb obscurely 2-lipped, 4-lobed. Drupe 5-6 mm in diameter, globose, black, collared below by slightly enlarged, persistent calyx.

Subshrubs ca. 9 cm tall. Rhizomes woody. Branches sparsely yellow-brown pilose or glabrous. Leaves rosulate; leaf blade obovate-oblong to spatulate, 3-14 X 2-6(-9) cm, sparsely pubescent and yellow glandular, base cuneate, margin sparsely serrate to sparsely crenulate above middle or rarely entire, apex rounded. Inflorescences paniculate capitate corymbs, 1-2.3 X 1-2.4 cm, ca. 10-flowered; peduncle 5-13 mm, densely puberulent; bracts linear to lanceolate, 3-8 mm. Calyx cup-shaped, ca. 2.5 mm, outside pubescent and yellow glandular. Corolla purple in bud, white in bloom, slightly 2-lipped, 4-lobed, outside puberulent. Ovary 2-locular. Fruit ca. 5 X 4 mm. Fr. Jun.

Distribution: Sub-Himalayan tracts, India and Bangla Desh.

Hainan, W Yunnan [Bhutan, Cambodia, India, Laos, Myanmar, Nepal, New Guinea, Philippines, Thailand, Vietnam; Australia].

Fl. Per.: Feb.-April.

Dry places; 200-1700 m.

Premna humilis Merrill; P. nana Collett & Hemsley; P. obovata Merrill; Pygmaeopremna herbacea (Roxburgh) Moldenke.

Premna herbacea là một loài thực vật có hoa trong họ Hoa môi. Loài này được Roxb. miêu tả khoa học đầu tiên năm 1832.