Accepted name: Dendrochilum luzonense Ames, Orchidaceae 2: 121 (1908)



Subgenus – Acoridium. Section – Acoridium.


 
 
 

Synonyms

Acoridium luzonense (Ames) Ames, Orchidaceae 7: 81 (1922).

Origin in the Wild

 

Luzon

 

Elevation in the Wild

 

1600-2600 metres

 

Habitat in the Wild

 

The holotype was collected in Benguet province on the trail to Balbalasan. This species has been collected in Benguet Province on Mount Pangualitikai and Ifugao Province on Mount Polis. Within Ilcos Norte province this species has been collected from Mount Burnay. In Kalinga-Apayao province a plant has been collected on Mount Sulu although its identification is uncertain.

 

This plant has been collected as an epiphyte in mossy forest.

 

The Plants Description

 

The pseudobulbs cluster together on a short rhizome and are shaped terete. The pseudobulbs measure 4.2-14.5cm long and 0.1-0.2cm in diameter. The pseudobulbs are covered by c6 cataphylls while they are growing. The cataphylls disintegrate into persistent fibres as the pseudobulbs mature. The leaves are not truly petiolate. The leaf blades are shaped narrowly linear-filiform and have acute apices. The leaf blades measure 14.9-44.2cm long and 0.1-0.2cm wide. The leaves have 1 distinct nerve.

 

The Inflorescence

 

The peduncle is enclosed for almost all of its length by the subtending leaf and appears to grow from its distal section. The peduncle is suberect to curving and measures 13.9-30cm long. The peduncle is triangular in cross-section. The rachis is nodding to pendent and measures 3.8-6cm long. The flowers alternate distichously and are spaced 1-2mm apart. There are 1-5 appressed non-floriferous bracts at the base of the rachis. The flowers open at the same time.

 

The Flowers

 

The flowers are whitish-yellow to orange-yellow and have a red-brown rostellum. The dorsal sepal is shaped lanceolate-oblong and has an acuminate-acute apex. The dorsal sepal measures 3.7-5.5mm long and 1.1-1.3mm wide. The dorsal sepal is three veined and has an entire margin. The lateral sepals are shaped obliquely triangular-oblong to lanceolate and have subacuminate apices. The lateral sepals measure 3.5-5.5mm long and 1.4-1.8mm wide. The lateral sepals are three veined and have entire margins. The petals are shaped oblong-lanceolate and have acuminate to acute apices. The petals measure 3.3-4.9mm long and 0.8-1.9mm wide. The petals are three veined (rarely one veined) and have entire margins that can be serrated towards their apices. The labellum is porrect and is 3-lobed. The labellum measures 0.9-1.2mm long and 1.8-2.4mm wide. The labellum is obscurely three veined, glabrous and has entire margins. The side lobes are erect, shaped broadly and obliquely elliptic and have subacuminate apices. The side lobes are an equal length to the mid-lobe. The mid-lobe is shaped semiorbicular to transversely rectangular and has an obtuse apex that is sometimes minutely mucronate. There are two rounded calli located at the base of each side lobe, the median callus is located in between the lateral calli and situated in the centre of the disc. The median callus is an oblong circle shape. The column is straight and clavate and measures 0.8-1.1mm long; the column is somewhat hooded. The small apical hood has two teeth at its apex; one of the teeth pointing forwards. Stelidia and column foot are absent.

 

Herbarium Specimens

 

Holotype

 

AMES

 

Specimen 18824 (photo)

 

 

Isotype

 

Royal Botanic Gardens, Kew (K)

 

I could not locate the specimen

 

 

Other herbarium specimens

 

National Herbarium Netherlands (L)

 

Specimen L0322630

 

Scent

 

Yes, Pedersen describes the plant as fragrant.

 

Flowering Season

 

Flowering plants have been collected in the wild during February and from October to December.

 

Culture

 

This species is in cultivation but not common.

 

Similar Species

 

Dendrochilum williamsii

 

Other Information

 

Ames wrote that this species was the nearest ally to Dendrochilum williamsii. L.O. Williams wrote that this species had no close relatives. Henrik Pedersen agreed with Ames and wrote that Dendrochilum luzonense should be considered the sister species of Dendrochilum williamsii.

 

Reference -

 

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

 

World Checklist of Selected Plant Families. 20 January 2009. The Board of Trustees of the Royal Botanic Gardens, Kew. Published on the Internet; http://www.kew.org/wcsp/ accessed 20 January 2009.