ORCHIDACEAE
Apostasia Blume, Bijdr. Fl. Ned. Ind.: 423 (1825).
By: Bhakta B. Raskoti
Taxon Description
Terrestrial herbs. Rhizome scaly, producing stout roots. Stem simple or branched, slender, leafy. Leaves clustered, plicate, base sheathed. Inflorescences terminal or subterminal, often arching, branched, laxly flowered. Flowers only half opening. Sepals similar, free. Petals similar to sepals. Lip similar to petals, slightly larger in size. Column erect or curved, with 2 fertile stamens, with a central staminode; anthers 2 loculed; filaments adnate to style; staminode opposite to dorsal sepal; pollen not sticking together; style cylindric; stigma capitate, terminal. Fruit a cylindrical capsule.
Taxon Statistics
Worldwide 8 species, distributed in E Asia, S Asia, SE Asia and Australasia. One species in Nepal.
1. Apostasia wallichii R. Br. in Wallich, Pl. Asiat. Rar. 1: 75 (1830).
Apostasia alba Rolfe; Niemeyera stylidioides F.Muell.
Plants 20–30 cm tall. Rhizome stout with fibrous woody roots. Stem suberect, base usually prostrate, with several tubular sheaths at base. Leaves linear to sublinear, 7–15 × 0.5–1.3 cm, apex acuminate, awned; petiole-like stalk 1.5–3 cm. Inflorescence racemose or with a few lateral branches, 6–10 cm, arising from distal leaf axils, recurved or suberect, more than 10-flowered. Peduncle bracts lanceolate ca. 4–5 × 1 mm, apex acuminate. Floral bracts lanceolate, 3–5 × 1–1.5 mm, apex acuminate. Flowers yellow, 5–8 mm across; pedicel and ovary 15–20 mm. Dorsal sepals oblong-lanceolate, 5–8 × 1–1.5 mm, apex mucronate. Lateral sepals oblong-lanceolate, 5–8 × 1–1.5 mm, apex mucronate. Petals similar to sepals, 5–7 × 1–1.5 mm. Lip linear-oblong, 5–8 × 1–1.5 mm, apex mucronate. Column wingless, 4–6 mm; filaments erect, ca. 4–5 × 0.5–1 mm; anther oblong, 2–3 mm, base sagittate; staminode subcylindric, adnate to style, apical ca. 0.5 mm free; style ca. 3.5–4 mm, stigma dilated. Capsule cylindric-fusiform, 15–20 × 1–1.5 mm.
Distribution: Nepal, E Himalaya, Assam-Burma, E Asia, S Asia, SE Asia and Australasia.
Altitudinal range: 600–1000 m.
Ecology: Terrestrial, among litter in broadleaved forests.
Flowering: August. Fruiting: September–November.