Phalaenopsis cacharensis (Barbhuiya, B.K.Dutta & Schuit.) Kocyan & Schuit.

Kew Species Profiles

General Description

Ornithochilus cacharensis is a small orchid with bright red-purple flowers opening from June to October. Its growth habit is monopodial (it continues to grow each year from the same growing point). Only one plant has been recorded, and it is considered to be Critically Endangered.

Ornithochilus is closely related to the well-known genus Phalaenopsis (moth orchids) and will in the future be combined with the latter.

Species Profile

Geography and distribution Inflorescence of Ornithochilus cacharensis (Photo: H. A Barbhuiya, Botanical Survey of India)

Ornithochilus cacharensis has only been recorded in Cachar district, Assam, India.

The single recorded individual was found growing as an epiphyte on the trunk of a Duabanga grandiflora in wet evergreen lowland forest at about 130 m above sea level. It was growing in association with Piper species.

Description

Overview: Monopodial (growing from the same point each year) epiphyte (growing on another plant for support). Roots circular in cross-section, 2.5-3.0 mm in diameter.

Stems: Unbranched, 2.0-3.5 cm long.

Leaves: Mid-green, twisted at the base, elliptic-oblong, 19.0-21.0 × 3.0-4.3 cm, with a sheathing base, 1.0-1.2 cm long.

Flowers: Red-purple, the lip darker than sepals and petals, about 1.7 cm in diameter. Borne in inflorescences 35-38 cm long, with 1-4 branches, containing about 30-70 flowers. Lip four-lobed, with a curved spur about 4.2 mm long situated in the middle of the lip. Column red-purple, hairless, 6.2-6.5 mm long, with the ventral side whitish. Pollinia (distinct masses of pollen grains) yellow and four in number (in two pairs).

Fruits: Unknown.

Kew scientist works with partners to publish new orchid species

During recent fieldwork in the eastern part of the Borail Wildlife Sanctuary, in the Cachar district of Assam, H. A. Barbhuiya (Botanical Survey of India) discovered a single, mature individual of a small, monopodial orchid with bright red-purple flowers. It was described as a new species,  Ornithochilus cacharensis , in a 2012 issue of  Kew Bulletin , in collaboration with partners including Kew scientist André Schuiteman.

Its specific epithet  cacharensis  was given in honour of the district (Cachar) where it was found.

How this species differs from others in the genus

The column of Ornithochilus cacharensis differs from that of O. difformis in being twice as long and hairless.

The margins of the lip epichile (terminal divisions of the lip) are sharply toothed, in contrast to the small, rounded teeth of O. yingjiangensis .

Ornithochilus cacharensis differs from both of these species in its uniformly red-purple flowers and the relatively longer lateral lobes of the lip hypochile (basal part of the lip).

Threats and conservation

Ornithochilus cacharensis has been assessed as Critically Endangered according to IUCN criteria. Only a single plant has been recorded, and its habitat is threatened by slash-and-burn cultivation and tree-felling.

This species at Kew

Dried and alcohol-preserved specimens of the related species Ornithochilus difformis are held in Kew's Herbarium. The details of some of these can be seen in Kew's Herbarium Catalogue.

Distribution

India

Ecology

Epiphytic (on the trunk of Duabanga grandiflora) in wet evergreen lowland forest.

Conservation

Critically Endangered (CR) according to IUCN Red List criteria. Only one plant has been recorded.

Hazards

None known.