Tuesday 5 April 2016

Epiphytic Orchids from the Lengguru Fold Belt of West Papua.

The island of New Guinea is home to about 11% of the world's described Orchids, over 2700 species, giving it the richest known Orchid diversity outside the rainforests of the equatorial Andes. However this known diversity is probably a poor reflection of the actual diversity present, as many areas of the island have only been very briefly surveyed by botanists.

In a paper published in the journal PhytoKeys on 25 February 2016, Lina Juswara of the Herbarium Bogoriense of the Indonesian Institute of Sciences, André Schuiteman of the Royal Botanic Gardens, Kew, and Vincent Droissart of the Institut de Recherche pour le Développement, the Africa & Madagascar Department of the Missouri Botanical Garden and the Herbarium et Bibliothèque de Botanique africaine of the Université Libre de Bruxelles, describe four new species of epyhytic Orchids (Orchids that grow on larger plants) from the Lengguru Fold Belt, a range of mountains connecting the Central Range of western Papua to the mountain's of the Bird's Neck Peninsula.

The first new species described is placed in the genus Bulbophyllum, a large and diverse group of Orchids found throughout the tropics, but thought to reach its maximum diversity ion New Guinea, and given the specific name leucoglossum, meaning 'white tongue' in reference to the white lip of the flower. This Orchid grows from a creeping rhizome, producing dark green oval leaves, and single dark red and white flowers. It was found growing in submontane forest in the Kumawa Forest Reserve at an altitude of 1005 m. The plants were growing about 150 cm above the ground on a Moss-covered overhanging tree-trunk.

Bulbophyllum leucoglossum: (A) Habitat and habit, (B) flower, side view (C) flower, front view, (D) flower close-up, showing details of the column and the labellum. Vincent Droissart in Juswara et al. (2016).

The second new species described is placed in the genus Dendrobium, another widespread genus, found from Australia to Southeast Asia, comprising exclusively epiphytic Orchids, and given the specific name centrosepalum, meaning 'sharply pointed sepals', in reference to the stucture of the flower. This is another rhizomatous Orchid, producing narrow elliptic leaves and bracts with an average of seven bright purple flowers. It was found at a single locality in Triton Bay near the village of Lobo, growing from a thick layer of Lichen and Moss covering a vertical tree trunk, in submontaine forest at an altitude of 1114 m.

Dendrobium centrosepalum: (E) Habitat and habit, (F, G) plant and inflorescence, (H) inflorescence and flowers close-up. Vincent Droissart in Juswara et al. (2016).

The third new species described is also placed in the genus Dendrobium and given the specific name taeniocaule, meaning 'flattened stem'. This is another rhizomatous epiphyte, with dark green oblong leaves and flattened stems, producing white flowers. It was found growing at a single location in Triton Bay near the village of Lobo, growing from a thick layer of Lichen and Moss covering a vertical tree trunk, in submontaine forest at an altitude of 1114 m.

 Dendrobium taeniocaule: (A) Habitat and habit, (B) plant, (C) flower and part of pseudobulb, (D) flower, front view (E) flower, side view. Vincent Droissart in Juswara et al. (2016).

The final new species named is placed in the genus Taeniophyllum, a widespread genus found from Southeast Asia to Australia, with species also known from China, India and Africa, and is given the specific name pyriforme, meaning 'pear shaped', in reference to the shape of the spur (hollow spike behind the flower). This is a leafless Orchid producing numerous elongate, flattened, unbranching roots from a single stem. It produces up to three yellowish-white flowers. This Orchid was also was found growing at a single location in Triton Bay near the village of Lobo, growing from a thick layer of Lichen and Moss covering a vertical tree trunk, in submontaine forest at an altitude of 1114 m.

 Taeniophyllum pyriforme: (F) Habitat and habit, (G) plant and inflorescence, (H) inflorescence and flowers close-up. Vincent Droissart in Juswara et al. (2016).

See also...

http://sciencythoughts.blogspot.co.uk/2015/08/gastrodia-madagascariensis-not-so-new.htmlGastrodia madagascariensis: A (not so) new species of parasitic Orchid from Madagascar. The German botanist Rudolf Schlechter published Orchidaceae Perrierianae, a description of all then known species of Orchids from Madagascar, including 332 new species based upon material supplied by...

http://sciencythoughts.blogspot.co.uk/2015/08/catasetum-telespirense-new-species-of.htmlCatasetum telespirense: A new species of epiphytic Orchid from the southern Brazilian Amazon.
In 2011-2012 a series of series of rescue expeditions recovered and relocated around 105 000 epiphytic plants (plants which live on other plants, typically...

Orchids of the genus Liparis are found across tropical Asia, New Guinea, the islands of the southwest Pacific and tropical and subtropical regions of the Americas. There are currently sixty five species known to grow...

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