| Bulbophyllum | |
|---|---|
| Bulbophyllum echinolabium | |
| Scientific classification | |
| Kingdom: | Plantae |
| (unranked): | Angiosperms |
| (unranked): | Monocots |
| Order: | Asparagales |
| Family: | Orchidaceae |
| Subfamily: | Epidendroideae |
| Tribe: | Podochilaeae |
| Subtribe: | Bulbophyllinae |
| Genus: | Bulbophyllum Thouars, 1822 |
| Species | |
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List of Bulbophyllum species
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| Synonyms | |
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Bulbophyllum is the largest genus in the orchid family Orchidaceae. With more than 2,000 species, it is also one of the largest genera of flowering plants, exceeded only by Astragalus.[1] This genus is abbreviated in the trade journals as Bulb.
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This genus was first described by Louis-Marie Aubert du Petit-Thouars (botanical abbreviation Thouars) in his book "Histoire particulière des plantes orchidées recueillies sur les trois Iles Australes d’Afrique, de France, de Bourbon et de Madagascar", describing 17 Bulbophyllum species. There are now more than 2,800 records (accepted names and synonyms) for this genus. This large number and the great variety of its forms make the genus a considerable challenge for the taxonomist: 120 sections and subgenera have been listed. Some of these may deserve a generic status. Several species have as many as ten synonyms. Up to now a general review of this genus is lacking. But as Carlyle A. Luer of Missouri Botanical Garden disentangled the similar chaos in the Pleurothallidinae, so we may expect that a phylogenetic study will gain us a better insight in this large genus.
The scientific name has been derived from the Latin word bulbus (bulb-like) and the Greek word phyllon (leaf), referring to the pseudobulbs on top of which the leaf is growing.
The center of diversity of this genus is in the montage forests of Papua New Guinea (more than 600 species) which seems to be the evolutionary homeland,[2] though the genus is pantropical and widespread, occurring in Australia, Southeast Asia (with over 200 species in Borneo), India, Madagascar (with 135 species, some endemic), Africa and in tropical central and South America.
The general characteristics for this genus are : single-noded pseudobulbs, the basal inflorescence and the mobile lip.
This genus covers an incredible range of vegetative forms, from tall plants with cane-like stems, to root climbers that wind or creep their way up tree trunks. Other members are pendulous epiphytes (growing on other plants), and quite a number that have developed succulent foliage to a greater or lesser degree. Some species are lithophytic. One species has almost become leafless and uses its pseudobulbs as the organs of photosynthesis.
These orchids with a sympodial growth have rhizomatous stems with often angled pseudobulbs. The thin to leathery leaves are folded lengthwise.
Many Bulbophyllum species have the typical odor of rotting carcasses, and the flies they attract assist in their reproduction through pollination.
The erect to pendent inflorescence arises laterally from the base of the pseudobulb. The flower form has a basic structural blueprint that serves to identify this genus. But this form can be very diverse : compound or single, with few to many flowers, with the resupinate flowers arranged spirally or in two vertical ranks. The sepals and the petals can also be very varied : straight or turned down, without footstalk or with a long claw at the base. They are often hairy or callous. There are two to four hard and waxy pollinia with stipes present or absent. The fruits are beakless capsules.
Some species are known for their extremes of vegetive and floral form:
New species are being discovered every year, such as
Bulbophyllum nocturnum, a species first described in November 2011, is the only orchid known to flower at night.[3][4]
There is one intergeneric hybrid : Triasphyllum (abbr.: Tphm.) (Bulbophyllum x Trias)
A number of Bulbophyllum species are threatened with extinction, and are recognised as such by the World Conservation Union (IUCN):
Additionally, Bulbophyllum porphyrostachys is listed as near threatened.