Accepted name: Dendrochilum marginatum (Ames) L.O.Williams, Philipp. J. Sci. 80: 318 (1952)

Subgenus – Acoridium. Section – Acoridium.


 
 

Synonyms

 

Acoridium marginatum Ames, Schedul. Orchid. 6: 23 (1923).

 

Origin in the Wild

 

Luzon

 

Elevation in the Wild

 

1495 metres

 

Habitat in the Wild

 

This species has only been collected from Mount Irig in Rizal Province. Ames wrote that it was found as an epiphyte on trees (Ames 1923).

 

The Plants Description

 

The pseudobulbs cluster on a short rhizome and are shaped obpyriform to ellipsoid. The pseudobulbs measure 0.6-1.4cm long and 0.3-0.5cm in diameter. The pseudobulbs are covered by 3-4 cataphylls while they are growing. The cataphylls disintegrate into persistent fibres as the pseudobulbs mature. The leaves are petiolate, the petiole measures 0.7-2.9cm long. The leaf blades are shaped narrowly lanceolate to linear-lanceolate and have obtuse to finely mucronate apices. The leaf blades measure 3.2-13cm long and 0.4-1.1cm wide. The leaves have 3 distinct nerves; the 2 outermost nerves are submarginal.

 

The Inflorescence

 

The inflorescence is synanthous and is free from the subtending leaf at the time of flowering. The peduncle is suberect to curved and measures 6.8-15.8cm long. The rachis is nodding, somewhat flexuose and measures 4.1-8.5cm long. The flowers alternate distichously and are spaced 3-4mm apart. There are 3-4 non-floriferous bracts on the inflorescence. The flowers open from the proximal section of the rachis, although Ames wrote that the flowers open successively (Ames 1923).

 

The Flowers

 

The flowers are yellow and open widely (Ames 1923 and Pedersen 1997). Ames wrote that between 10 and 20 flowers grow on an inflorescence (Ames 1923). The dorsal sepal is shaped elliptic-oblong and has a rounded–obtuse apex. The dorsal sepal measures 3.6-4mm long and 1.8-2mm wide. The dorsal sepal has an entire margin and is three veined. The lateral sepals are shaped broadly and obliquely ovate and have a rounded-obtuse carinate apex which is often mucronate. The lateral sepals measure 3.4-3.8mm long and 2.2-2.5mm wide. The lateral sepals have entire margins and are three veined. The petals spread widely and are somewhat recurved. The petals are shaped broadly and obliquely spathulate and have rounded apices. The petals measure 3.7-3.8mm long and 3.2-3.4mm wide. The petals have entire margins and are three veined. The labellum is porrect and entire. The labellum is shaped oblong, widened towards its apex, usually hastate at its base, its apex is obtuse. The labellum measures 1.8-1.9mm long and c1.4mm wide. The labellum is obscurely three veined and has an entire margin. The lateral calli are minute swellings and there is no median callus. The column is suberect and straight and measures 0.6-0.7mm long and hooded at the apex. The anther is broadly ovate from the upper view and rounded from the front.

 

Herbarium Specimens

 

Holotype

 

AMES

 

Specimen 37 (photo)

 

Scent

 

I could find no record

 

Flowering Season

 

Flowering plants have been collected in the wild during April.

 

Culture

 

I do not think this species is in cultivation.

 

Similar Species

 

Dendrochilum foxworthyi

Dendrochilum philippinense

Dendrochilum rhombophorum

Dendrochilum macgregorii

 

Other Information

 

Ames wrote (1923) that this species was most similar to Dendrochilum rhombophorum and differed by its larger flowers and different labellum. Ames wrote that it differed from Dendrochilum irigense by its marginate leaves. These two species are now considered to be in 2 different sections of the subgenus Acoridium.

 

Henrik Pedersen groups this species with the other species above. L.O Williams considered this species to be a close ally of Dendrochilum turpe, now that the recognition of ptyxis is defining as a character the 2 species are placed in different sections.

 

Reference

 

AMES, Oakes. 1923, New and Noteworthy Orchids, Schedulae Orchidianae, No 6. Massachusetts, Boston.

 

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

 

World Checklist of Selected Plant Families. 29 October 2008. The Board of Trustees of the Royal Botanic Gardens, Kew. Published on the Internet; http://www.kew.org/wcsp/ accessed 29 October 2008.