Dendrobium aloifolium

Dendrobium aloifolium (Blume) Rchb.f., in Walp., Ann. Bot. Syst. 6 (1861) 279.

Basionym: Macrostomium aloifolium.

Roots few from stem base, <10 cm by 1 mm, smooth, white, stiff and wiry, branched. Rhizome very short. Stem erect to sprawling, 55-105 mm, with 9-19 leaves; lowest node swollen to 3 mm long and 2 mm wide, covered in fibrous sheath remnants; next 2-3 nodes cylindrical-conical, 1-2 mm wide, slightly compressed, remainder of stem obscured by sheathing leaf bases, broadens to c. 4 mm wide in mid-stem then decreases to c. 1.5 mm at apex, sinuous, strongly compressed, nodes 5-8 mm apart. Leaves distichous, laterally compressed, held at c. 45 degrees to stem, oval, longest in mid-stem, to c. 1.7 cm by 7.5 mm, thick and succulent, very leathery, acute apex sharp pointed; sheaths equitant, longer than internode, non-deciduous, upper margin membranous. Inflorescences arising from the stem apex, from a compressed 1-2 mm wide oblong bundle of erect to deflexed 4-6 mm long dry brown scales which produce single descending flowers in succession. Peduncle c. 1 mm long, obscured by scales, cylindrical. Pedicel and ovary descending, 3 mm long, cylindrical, smooth. Flower 4 mm long by 3.5 mm wide, fleshy and stiff, sepals and petals strongly recurved. Dorsal sepal oblong, 2.6 by 1.3 mm, abaxially broad ridged; apex tridentate, the broad acute-tipped mucro projects beyond lateral teeth. Lateral sepals 4 mm long, free part 2.4 by 1.6 mm, oblong, apex rounded, minutely retuse; mentum cylindrical, 1.6 mm long, obtuse, laterally inflated. Petals linear, 2.2 by 0.7 mm, forward margins erose, apex obtuse apiculate. Lip porrect, 4 mm by 1.8 mm, obscurely 3-lobed; base subsaccate, then broadly cuneate to lip centre, then narrowing to midlobe, gutter-shaped; midlobe subcircular c. 1 mm long, depressed in centre, almost completely divided into 2 irregular broadly overlapping lobes, raised margins erose and undulating; lip floor thick and fleshy,
broadens abruptly in centre to form a raised callus that occupies front half of lip behind midlobe. Column c. 1 mm long, broad, arms short and rounded; foot 1.6 mm, parallel to column, raised in centre, apex decurved. Pollinia 4 in 2 pairs, without appendages. Anther 2-celled.
(after O'Byrne, 1994).

Colours: Sepals and petals off-white sepals, lip white fringed faint purple; column greenish-white column, anther green.

Habitat: Epiphytes lowland rainforest and hill forest. Altitude 0 to 550 m.

Flowering time in the wild: Throughout the year. Flowers last 10 to 20 days (fide O'Byrne).

Distribution: Burma, Thailand, Laos, Cambodia, Vietnam, Peninsular Malaysia, Singapore, Sumatra, Java, Borneo, Lesser Sunda Islands, New Guinea, the Philippines.

Distribution in New Guinea: Papua New Guinea (Madang and Central Provinces).

Notes: Of all the Dendrobium species in New Guinea with laterally flattened leaves, Dendrobium aloifolium has perhaps the smallest flowers. Next to Dendrobium inconspicuum it is probably the only true species of section Aporum known from New Guinea, the other New Guinea species referred to this section are probably better placed in section Crumenata.

Cultivation: Easy to grow either in a small pot of bark/stone/fibre mixture or on a tree-fern or wood slab. Needs warmth, bright scattered light and regular water (fide O'Byrne).