Calanthe arfakana

Calanthe arfakana J.J.Sm., Repert. Spec. Nov. Regni Veg. 11 (1913) 555

Type: Gjellerup 1072 (holo BO)

Pseudobulbs very small, 2-3-leaved. Leaves petiolate, elliptic or oblong-elliptic, acutely acuminate, laxly undulate and minutely crispate, glabrous, with 5 larger, underneath prominent nerves and numerous thinner nerves, 6-14 by 2-4.5 cm wide; petiole short, channelled, strongly 5-ribbed, including the short tubular sheath 2.2-3 cm long. Inflorescence 1, axillary, erect, strongly elongated, laxly many-flowered, peduncle terete, densely puberulous, 47.5 cm long, 0.3 cm diam., with two tubular, obtuse, puberulous, prominently veined, 1.4-2.1 cm long, small scales; rachis angular, grooved, densely puberulous, more than 9 cm long. Floral bracts persistent, ovate-lanceolate, obtuse, mostly apiculate, concave, puberulous, 5-nerved, to 1.1 cm long, 0.43 cm wide, upper ones smaller. Flowers very small, in total 1.63 cm long. Sepals and petals reflexed. Median sepal broadly elliptic, obtuse, convex, dorsally slightly puberulous, 5-nerved, 0.65 by 0.4 cm. Lateral sepals obliquely elliptic, obtuse, subapiculate, concave, 5-nerved, dorsally slightly puberulous, 0.66 by 0.37 cm. Petals obliquely spathulate, obtuse, convex, glabrous, 2-nerved, inside and outside longitudinally 1-grooved, 0.6-0.63 by 0.2 cm or slightly over 0.2 cm wide, claw cuneate-dilated into the oblong, about twice as long blade. Lip 3-lobed, spurred, for 0.38 cm adnate to the column forming an oblique, outside on either side on one side of the suture puberulous, inside pilose tube; spur pointing backwards, making an acute angle with the ovary, slightly curved, terete, underneath towards the apex longitudinally grooved, at the apex retuse, glabrous, 0.68 cm long; blade porrect, inside near the base between the lateral lobes with three short, longitudinal, strong, warty-rugose, at the back pilose (with backwards pointing hairs) keels, median keel a little longer than the outer ones, all 3 prolonged in a low, subverrucose rib that does not reach the apex of the claw of the mid-lobe; blade when flattened 0.85 by 1.1 cm; lateral lobes deflexed, obliquely quadrangular-oblong, towards the apex somewhat obliquely dilated, obliquely truncate, at the apex slightly wavy, in front obtuse, convex, 0.45 cm long, almost 0.3 cm wide; mid-lobe porrect, convex, bilobulate, clawed-cuneate, sinus acute, with a minute obtuse lobule in the sinus, 0.63 cm long, at the base 0.24 cm wide, in the apical part 0.58 cm wide, lobules divergent, obliquely oblong-quadrangular, obtuse, in front slightly wavy, 0.3 by 0.23-0.24 cm. Column along its entire length adnate to the lip, thickened towards the apex and dorsally convex, in front strongly oblique, dorsally 0.2 cm long, underneath 0.38 cm long; clinandrium deeply concave, transverse, subreniform, inside with a longitudinal rib, stigma lobes much surpassing the clinandrium, obliquely truncate. Anther cucullate, broadly obtuse, retuse, 0.16 cm wide. Pollinia 8, obliquely clavate. Rostellum much short than the stigma lobes, bilobulate, the lobules triangular, falcate. Ovary triangular, 6-grooved, densely minutely puberulous, 0.5-0.6 cm long, pedicel thinner, 6-grooved, twisted, 0.3-0.4 cm long. (After Smith, 1915).

Colours: Leaves dark green. Flowers greenish yellow.

Habitat: Terrestrial. Altitude 1900-3260 m.

Flowering time in the wild: January, April, June.

Distribution: Malesia (New Guinea, endemic).

Distribution in New Guinea: Papua (Indonesia); Papua New Guinea. See map: 101-23M.JPG

Cultivation: Cool growing terrestrial, requires shaded position.

Note: This is one of the more common species of Calanthe in New Guinea. Some of the species described by van Royen and Gilli will almost certainly prove to be synonymous with it. It is distinct from Calanthe flava (Blume) Morren by its much narrower leaves, among other things, and we believe records of C. flava from New Guinea to be erroneous.