Dendrobium habbemense

Dendrobium habbemense P.Royen, Alp. Fl. New Guinea 2 (1979) 424, fig. 147.

Type: Brass 9022 a (holo L).

Pendulous, epiphyte up to 100 cm long. Roots 1-2.5 mm diameter, white. Stem(s) 10-100 by 0.2-0.7 cm, pendent, curving, usually only a single slender stem at base, branching above and often thickening towards apex, nodes 0.3-3 cm apart, leafy towards apex. Leaves 1-10 by 0.2-0.8 cm, pendent to slightly spreading (more spreading and becoming plicate when exposed), linear, usually falcate, acute; sheaths warty (papillate). Inflorescences 1-10, single flowered (very rarely 2-flowered), spaced along apical part of stem just behind the leafy section, sessile; bracts cup-like with longer side apiculate, warty (resembling the bracts of Dendrobium cuthbertsonii ), old bracts very persistent. Flowers 2.2-4.2 cm long, usually widely opening (to 3.6 cm broad). Median sepal 9-17 by 4-8 mm, subrhombic-elliptic to ovate-elliptic, acute. Lateral sepals 18-36 by 6-12 mm, obliquely triangular, acute; basal fused part 2-7 mm long (proportionately short for section), conical in side view; mentum total length 13-24 mm, falcate, tip obtuse. Petals 8-16 by 2-5 mm, narrowly oblong-elliptic, subacute. Lip 19-35 by 6-12 mm, simple, spathulate-rhombic, obtuse to acute, adnate to column foot at base, not fused to lateral sepals, central margins up to widest part of lip incurved. Column 4-6 mm long; foot 13-24 mm long; anther 2-4 mm broad; pollinia 1-2 mm long. Ovary regular, slightly 6-ribbed; pedicel and ovary 15-33 mm long. Fruit not observed.
(after Reeve & Woods, 1989).

Colours: Leaves usually purplish. Flowers bright orange to orange-red (usually mentum is reddish to maroon).

Habitat: Low pendulous epiphyte in montane and alpine forest and shrubberies. Altitude 2100 to 3500 m.

Flowering time in the wild: August to January.

Distribution: New Guinea.

Distribution in New Guinea: Papua (Mt. Carstenz and Mt. Trikora); Papua New Guinea (Enga, Southern Highlands, Western Highlands, Simbu, Eastern Highlands, Madang, Morobe and Central Provinces).

Map: HABBEMAP.JPG [Dendrobium habbemense P.Royen, distribution map, redrawn from T.M. Reeve & P.J.B. Woods, Notes Roy. Bot. Gard. Edinburgh 46 (1989) 285, map 7.]

Notes: Dendrobium habbemense is a distinctive species, with no close allies. Characteristics of this species to be noted are its pendulous curving habit, the very slender stem at the base becoming thicker apically, the persistent warty cup-like floral bracts and single-flowered inflorescences, the usually widely opening flowers and the spathulate-rhombic lip.

Dendrobium habbemense almost always grows in shaded habitats as a low epiphyte. The type (Brass 9022A ) was collected from an exposed alpine position, and is therefore much shortened with the leaves becoming plicate. An interesting feature of this species is that flower size, as a general rule, is observed to be larger at higher altitudes.

This species has a wide distribution in New Guinea, its most westerly record being from Mt. Carstenz, but although widespread it is not common except in a few localities such as Mt. Giluwe and Mt. Wilhelm in Papua New Guinea.

Cultivation: Dendrobium habbemense, being suspended by a single slender stem, and rooting only at the base is a very difficult species to establish and cultivate. It requires cool conditions throughout the year and should be kept in a shaded position.