Ceratostylis Blume, Bijdr.: 304 (1825).
By: Devendra M. Bajracharya & L.R. Shakya
Taxon Description
Plants epiphytic or lithophytic herbs. Stubby rhizome short or rather long, creeping or pendulous and many fibrous roots. Pseudobulb absent. Stems crowded, pendulous, simple and rush-like or branched, sheathed, sheaths reddish brown or pale reddish brown. Leaf solitary, narrow, coriaceous, fleshy to subterete, petiolate, narrowly linear, leathery, fleshy or subterete. Inflorescence terminal, usually clustered flowers, with 2-3 flowers, sometimes only 1; the floral bract small; stalk and pedicel pubescent. Flowers small, resupinate, white spotted with purplish red, suffused with purple, hairy externally, pedicel and ovary less pubescent. Sepals subequal, connivent; lateral sepals adnate at base to column foot forming a saccate or spurlike mentum. Column short, dilated above, apex bilobed or with 2 spatulate erect arms, foot long; anther terminal, incumbent, pollinia 8, in 2 groups, waxy, sessile, commonly adhering to a small viscidium. Capsule ovoid or ellipsoid.
Taxon Statistics
Worldwide about 100 species, distributed in tropical Asia to SE Asia. One species in Nepal
1. Ceratostylis himalaica Hook. f., Fl. Brit. India 5: 826 (1890).
Ritaia himalaica (Hook. f.) King & Pantl.
Plants epiphytic or lithophytic, 6–19 -cm tall. Stubby rhizome many fibrous roots. Stem pendulous, (1.5–) 2–7 cm, sub-dichotomously branched, short, completely sheaths, sheaths reddish brown or pale red-dish brown. Leaves solitary, linear or narrowly oblong, 2.5–7 mm, acuminate or acute, fleshy, obliquely notched, short petiole3–4 mm long. Inflorescence arising from leaf base, sub-capitate, 1- or 2-flowered, peduncle with 2 sheaths. Pedicel and ovary ca. 4 mm, pubescent. Floral bract ovate, 4–5 × 1.5–2 mm long, acute to acuminate, sheathing. Flowers 1 or 2, 3–4 mm across small, white spotted with purplish red, suffused with purple, hairy externally, pedicel and ovary 2–3 mm long. Sepals ovate-lanceolate, ca. 5-6 mm long, obtuse. Dorsal sepal oblong-ovate to ovate-lanceolate, 5–6 × 2–3.5 mm, obtuse, concave, pubescent outside. Lateral sepals broadly ovate-lanceolate, 3.5–4 x 2.7–3 mm, acute or acuminate, incurved abaxially pubescent, connate at the base to form a saccate mentum, ca. 3 mm long. Petals linear, sub-oblong, 3.5–4.5 x 0.8–1 mm, acute, glabrous. Lip unlobed, sub-orbicular, 2–3 mm long, obtuse, fleshy, emarginate, thickened, base deeply saccate, apex with a cushion like callus, disk slightly hairy. Column ca. 3 mm long, very short, apical arms horn-shaped. Capsule 5–7 mm, oval or ellipsoid.
Distribution: Nepal, E. Himalaya, China and SE Asia.
Altitudinal range: 900–1700 m.
Ecology: Epiphytic on tree trunks in evergreen forest.
Flowering and fruiting: April–June.