Accepted name: Dendrochilum binuangense Ames, Orchidaceae 6: 281 (1920)


Subgenus – Acoridium. Section – Acoridium.

 

 

 

 

Synonyms

 

Acoridium binuangense (Ames) Ames, Orchidaceae 7: 80 (1922).

 

Origin in the Wild

 

Luzon

 

Elevation in the Wild

 

500 metres

 

Habitat in the Wild

 

This species has only been collected from Mount Binuang in Quezon Province. The type specimen was recorded as growing as an epiphyte on a tree on the summit of Mount Binuang.

 

The Plants Description

 

The pseudobulbs cluster on a short rhizome and are shaped fusiform. The pseudobulbs measure 0.7-1.4cm long and 0.2-0.3cm in diameter. The pseudobulbs are covered by 2-3 cataphylls while they are growing. The cataphylls disintegrate into persistent fibres as the pseudobulbs mature. The leaves are petiolate; the petiole measures 0.2-1cm long. The leaf blades are shaped linear-oblong to narrowly elliptic and have obtuse apices. The leaf blades measure 3-6.8cm long and 0.8-1.2cm wide. There are 3 distinct nerves on the blades; the 2 lateral nerves are c1mm from the leaf margin.

 

The Inflorescence

 

The inflorescence is synanthous and free from the subtending leaf at the time of flowering. The peduncle is suberect or curved and measures 2.3-8cm long. The rachis is probably pendent and measures 3.0-10.6cm long. The flowers alternate distichously and are spaced 1.5-2.0mm apart. There is a single non-floriferous bract on the rachis. The flowers open from the proximal section of the rachis.

 

The Flowers

 

The flowers are white. The dorsal sepal is shaped linear-lanceolate and has an acuminate apex. The dorsal sepal measures 3.6-3.9mm long and 1-1.3mm wide. The dorsal has entire margins and is 1-veined. The lateral sepals are shaped broadly lanceolate and have acuminate apices. The lateral sepals measure 3.6-3.9mm long and 1.0-1.3mm wide. The lateral sepals have entire margins and are 1-veined. The petals are shaped linear-lanceolate and are somewhat acuminate at their apices. The petals measure 3.3-3.4mm long and c0.7mm wide. The petals have entire margins and are 1-veined. The labellum is porrect and 3-lobed. The labellum measures c0.7mm long and c1.4mm wide. The side lobes are erect and shaped flabellate with a rounded apex. The side lobes exceed the mid-lobe. The mid lobe is shaped subquadrate and has a 3 dentate apex. The margins on the labellum are entire and there are no distinct nerves. The lateral calli are located at the base of the side lobes and are located on the front margin. The median callus is narrowly oblongoid and located at the centre of the disc. The column is suberect and slightly incurved. The column measures 0.9-1.0mm long. The column is not hooded at its apex. The anther cap is transversely elliptic from its upper view and obtuse from its front.

 

Herbarium Specimens

 

Holotype

 

AMES

 

Specimen 18866 (photo)

Specimen 98756 (drawing)

 

Isotype

 

New York Botanical garden (NY)

 

Specimen 39522

 

BM

 

Royal Botanic Gardens, Kew (K)

 

I could not locate the specimen

 

P

 

SING

 

US

 

W

 

Scent

 

I could find no record.

 

Flowering Season

 

Flowering plants have been collected in the wild during May.

 

Culture

 

I do not think this species is in cultivation

 

Similar Species

 

Dendrochilum asperum

Dendrochilum parvulum var parvulum

Dendrochilum parvulum var strictiforme

Dendrochilum mindanaense

Dendrochilum microchilum

Dendrochilum quadrilobum

Dendrochilum abortum

 

Other Information

 

Oakes Ames wrote “Dendrochilum binuangense at first glance resembles Dendrochilum microchilum so closely that it might readily be mistaken for it. The floral bracts are acuminate and end in a sharp triangular point, and the lateral lobes of the labellum are conspicuously longer than the middle lobe, exceeding the column when erect. In Dendrochilum microchilum, on the other hand, the floral bracts are obtuse and the lateral lobes of the labellum are not much longer than the middle lobe” (Ames 1920). Henrik Pedersen agreed with Oakes Ames and placed Dendrochilum binuangense in a group with those others named above. They are grouped because of the similarities of the labellum, vegetative similarities and a peduncle that is free from the subtending leaf at the time of flowering.

 

I have used Henrik Pedersen’s measurements rather than Oakes Ames; the reason being is that more specimens have been collected since its original collection in 1917.

 

Reference

 

AMES, Oakes. 1920, Illustrations and studies of the Family Orchidaceae Facsimile 6 The Orchids of Mount Kinabalu British North Borneo, Ames Botanical Laboratory, North Easton, Massachusetts, Boston.

 

PEDERSEN, Henrik. 1997, The Genus Dendrochilum (Orchidaceae) in the Philippines – A Taxonomic Revision. Opera Botanica, Denmark

 

World Checklist of Selected Plant Families. 16 December 2008. The Board of Trustees of the Royal Botanic Gardens, Kew. Published on the Internet; http://www.kew.org/wcsp/ accessed 16 December 2008.