Mediocalcar bifolium J.J.Sm., Bull. Dép. Agric. Indes Néerl. 39 (1910) 17
Type: Römer, von 1322 (holo BO)
Roots densely covered with root-hairs, 0.5 mm thick. Rhizome erect, patent or pendulous, usually frequently branching, the branches often becoming more numerous distally, 1-1.5 mm thick. Cataphylls of the young shoot 3-5, closely appressed, glabrous, subacute, keeled near the tip. Pseudobulbs 0-15 mm apart, terete, 1-2 cm long, 1-2.5 mm across; base elongated, enveloping the rhizome; free part ascending to prostrate, usually much shorter than the basal part. Leaves mostly two per pseudobulb, but one-leaved pseudobulbs fairly frequent, rarely all pseudobulbs one-leaved, sessile to subpetiolate, linear to narrowly elliptic, flat to semiterete (index (3.7-)5-16(-22)), (1.5-)2.5-6(-11) cm by (2-)3-7(-9) mm; glabrous; apex obtuse, rarely acute, minutely bilobed, mucronate; margins entire; coriaceous to carnose. Inflorescences solitary, synanthous or heteranthous, at the base with an inconspicuous scale c. 1 mm long. Peduncle 5-15 mm long, at the apex with a triangular bract 1-1.5 mm long. Pedicel and ovary 7-11 mm long. Flowers urceolate, oblique, 8-10.5 mm long. Synsepalumum 9-11 mm long and (13.5-)15-18 mm wide when cut open and flattened; free tips spreading to recurved, c. 3 mm long, subacute to acute. Petals linear to narrowly elliptic (index 4.5-10.8), 6.5-8 by (0.6-)1.2-1.5 mm; apex acute; 1-3-nerved. Lip (6-)7-9 by (2-)2.5-3.5 mm in natural position, the blade broadly ovate-subcordate when flattened; claw (2.5-)3-4 by c. 1.5-2.5 mm, auricles usually conspicuous, rarely hardly developed, subpatent to recurved; apex acute, slightly recurved; margins erect,clasping the column; spur cucullate to saccate, rarely recurved, at most half as long as the claw, (1-)1.5-2 mm deep. Column broadly clavate to subspathulate, (4-)5-6.2 mm long, 2-2.7 mm wide at the apex, foot 0.6-1.5 mm long. Fruit narrowly cylindrical-clavate, 23-35 by 3 mm. (After Schuiteman, 1997)
Colours: Sepals usually bright red, but not rarely orange-red or pinkish red or brownish red, with pure white tips, often only the margins of the tips white, sometimes the tips pink. Petals and lip pale orange with white or pinkish tips. Very rarely the entire flower yellow. Leaves dull green, pseudobulbs dull green to dull purple.
Habitat: Epiphyte in mossy forest, also terrestrial in moss cushions in open but sheltered vegetation, e.g. along tracks; 760-3350 m.
Flowering time in the wild: January, February, March, April, May, June, July, August, September, October, November, December.
Distribution: Malesia (New Guinea, endemic).
Distribution in New Guinea: Papua (Indonesia); Papua New Guinea. See map: 436-11M.JPG.
Cultivation: Cool growing epiphyte, requires light shade.
Notes: Perhaps the most frequently encountered orchid in the mountains of New Guinea. It often grows together with the very similar Mediocalcar agathodaemonis, which however has green-tipped flowers, synanthous inflorescences only, and broader leaves & pseudobulbs.