Octarrhena trigona

Octarrhena trigona (J.J.Sm.) P.Royen, Alp. Fl. New Guinea 2 (1979) 746, fig. 258

Basionym: Chitonanthera trigona

Stems elongated, branched, straight, mainly rooting near the base, weakly flexuose, thin, subterete, to c. 28 cm long, internodes 0.3-1 cm long; roots rather thick. Leaves distichous, patent, equitant, laterally compressed, sublanceolate, margins subparallel, at the apex dorsally compressed, the compressed part marginate, in the basal part sloping and making an obtuse angle with the lower leaf, shortly subacute, on either side longitudinally grooved, carnose, 0.5-0.9 by 0.15-0.18 cm; sheaths tubular, as long as the internodes, at the apex obliquely truncate, in cross-section rhombic, on either side with two longitudinal grooves, at the apex 0.18 to almost 0.2 cm wide. Inflorescences axillary, rather densely several-flowered; peduncle erect, filiform, 1.8-2.8 cm long, with two small scales, the lower scale tubular with extended apex, the upper scale bract-like; rachis recurved, triangular, the side facing the flowers with two ribs decurrent from the margins of the bracts, slightly flexuose in more than one plane, finely warty, 1-2 cm long, internodes 0.2 cm long. Floral bracts patent, triangular, acutely acuminate, with irregular margins, conduplicate-concave, dorsally thickened in the middle, with membranous margins, dorsally finely warty, to 0.26 cm long. Flowers 7-13, in three rows, 0.45 cm wide. Sepals widely patent, connate in the basal 0.07 cm. Median sepal short-ovate, at the apex shortly contracted, obtuse, 1-nerved, 0.2 cm long, 0.23 cm wide. Lateral sepals obliquely orbicular-ovate, at the apex narrowed, obtuse, 1-nerved, 0.2 cm long and wide. Petals very small, transversely subovate-elliptic, broadly obtuse, convex, puberulous, 0.05 by 0.1 cm. Lip small, making an obtuse angle with the ovary and an acute angle with the column, broadly elliptic, rounded, at the base truncate, on either side with a very short backwards pointing, obtuse lobule, slightly convex, papillose-puberulous, 1-nerved, almost 0.2 cm long, 0.17 cm wide. Column above the base strongly recurved, dorsally compressed, in front in the basal part convex and hollowed out, with a longitudinal groove, 0.16 cm long, stigmatic surface contained in the basal hollow, which has a transverse slit-like opening; clinandrium conspicuously hollowed out, divided into two erect, broad, falcate-incurved, subquadrangular, strongly hollowed out, dorsally convex, papillose lobules. Anther cucullate, in outline transversely elliptic, 0.05 cm wide, 6-lobulate, thinly membranous, connective convex, suborbicular. Pollinia 8, of which 4 larger and oblong, 4 much smaller. Rostellum erect, triangular, acuminate. Ovary 0.1 cm long; pedicel 0.13 cm long. (After Smith, 1929)

Colours: Sheaths dull green. Flowers light orange to dull red-orange, lip darker orange, velvety; column somewhat bluish. Ovary and fruit light orange.

Habitat: Terrestrial in open subalpine vegetation; 3250 to 3260 m.

Flowering time in the wild: October.

Distribution: Malesia (New Guinea, endemic).

Distribution in New Guinea: Papua (Indonesia). See map: 486-54M.JPG.

Cultivation: Cool growing terrestrial, requires light position.