Angraecum ochraceum (Ridl.) Schltr.

Hermans, J., Verlynde, S., Rajaovelona, L. et al. New species and nomenclatural changes in Angraecum (Orchidaceae) from Madagascar. Kew Bull 75, 49 (2020). DOI: https://doi.org/10.1007/s12225-020-09902-7

Morphology General Habit

Slender epiphytic herb up to 14 cm high, roots glabrous to slightly verrucose, silvery white 2 – 3 mm in diam.; stem short, 1 – 3 cm long, c. 1 cm in diam., completely covered by the greenish brown corrugate leaf sheaths, with 3 – 7 leaves forming a broad fan

Morphology Leaves

Leaves ligulate, 4 – 11 × 0.5 – 1 cm, narrowed and conduplicate at the base, with a central groove a little revolute at the margins, unequally roundly bilobed at the apex, pale to dark green

Morphology Reproductive morphology Inflorescences

Inflorescence erect to erectly spreading, filiform, up to 11 cm, with 1 – 2 short tubular sheaths, with 1 or rarely 2 flowers

Morphology Reproductive morphology Inflorescences Bracts

Floral bract thin-textured, ovate, acuminate, 2 – 2.5 × 1 – 1.5 mm, brown

Morphology Reproductive morphology Flowers

Flowers with the lip uppermost, 22 – 32 × 10 – 14 mm, yellowish green to ochre yellow, somewhat lustrous

Morphology Reproductive morphology Flowers Pedicel

Pedicel and ovary subcylindrical, 4 – 9 × 0.5 – 1 mm, yellowish, strongly twisted, grooved, often with a some black scales within the grooves

Morphology Reproductive morphology Flowers Calyx

Dorsal sepal broadly lanceolate, acute, 4.5 – 7 × 1.8 – 3.1 mm Lateral sepals ovate, 4.8 – 7 × 1.9 – 3 mm, spreading, attenuate

Morphology Reproductive morphology Flowers Corolla

Petals lanceolate, 3.1 – 6.5 × 1.2 – 2 mm, spreading, attenuate

Morphology Reproductive morphology Flowers Labellum

Lip ovate to rhombic, obtuse to shortly acuminate at the tip, 5.2 – 6.8 × 2.5 – 3.5 mm, strongly concave to navicular, rarely with a few thin hairs towards the base; spur generally pendent but sometimes horizontal, 14 – 22 × 0.6 – 2 mm, subfiliform-cylindrical apex more or less thickened, sometimes with 3 elongate lobules

Morphology Reproductive morphology Flowers Column

Column short, rounded, 1.5 – 2 × 1.3 – 1.8 mm, with short angular lateral rostellum wings, stigma oval, c. 1 mm in diam. Anther cap oblate, 1 – 1.5 × 1 – 1.2 mm; pollinia 2, subglobose, c. 0.5 mm in diam., distinct, with a small viscidium on each, c. 0.5 mm long

Distribution

Madagascar. Widespread, in Antananarivo, AntsirananaFianarantsoa, Toamasina and Toliara provinces.

Ecology

In humid evergreen forest, montane forest, on trees in moss. Altitude 538 – 2010 m.

Conservation

Angraecum ochraceum is endemic to Madagascar, has a large distribution range and is widespread in Antananarivo, Antsiranana, Fianarantsoa, Toamasina and Toliara provinces. It occurs in some Protected Areas such as Ambatovy, Ambohitantely, Andasibe-Mantadia, Andohahela, Montagne d’Ambre and Ranomafana. This species is therefore assessed as Least Concern (LC).

Phenology

flowering time. September to March but mainly in February.

Note

The species is recognised by the almost stemless medium-sized plant with thin ligulate leaves arranged into a fan, long filiform inflorescence with 1 (rarely 2) flowers, the strongly concave lip and long spur thickened towards the apex. The epithet ochraceum refers to the ochre colour of the flowers; setipes presumably refers to the thin bristle-like inflorescence.

IUCN Red List of Threatened Species https://www.iucnredlist.org/species/64593934/87613596

Conservation

VU - vulnerable