Accepted name: Dendrochilum mearnsii Ames, Orchidaceae 2: 116 (1908).

Subgenus – Platyclinis. Section – Eurybrachium.


 
 

Synonyms

 

None

 

Origin in the Wild

 

Mindanao and Visayas (Negros Oriental)

 

Elevation in the Wild

 

1350-2800 metres

 

Habitat in the Wild

 

On Mindanao this species has been collected in Agusan del Norte on Mount Hilonghilong, in Bukidnon Province on Mount Lipa, Misamis Occidental Province on Mount Malindang.

 

On Negros Oriental this species has been collected on Mount Talines.

 

The plants have been collected in mossy forest.

 

The Plants Description

 

The pseudobulbs cluster on a short rhizome and are shaped fusiform. The pseudobulbs measure 1.1-3.6cm long and 0.2-0.7cm in diameter. The pseudobulbs are covered by 3-4 cataphylls while they are growing. The cataphylls soon disintegrate into persistent fibres as the pseudobulbs mature. The leaves are petiolate; the petiole measures 1.0-4.9cm long. The leaf blades are shaped lanceolate and have acute to obtuse apices. The leaf blades measure 4.5-10.3cm long and 0.7-1.6cm wide. The leaves are thin textured and have 3-7 distinct nerves.

 

The Inflorescence

 

The inflorescence is synanthous. The peduncle is suberect and measures 3.0-13.2cm long. The rachis is probably pendent and measures 4.8-8.6cm long. The flowers alternate distichously and are spaced 1.0-2.0mm apart; the rachis twists to form a cylindrical spiral. There is one appressed non-floriferous bract at the base of the rachis. The flowers open from the proximal section of the rachis.

 

The Flowers

 

Henrik Pedersen wrote (1997) that the flower is dull salmon pink to purplish red and rarely white. The sepals and petals spread widely. The dorsal sepal is shaped oblong and has an acute, often mucronate apex. The dorsal sepal measures 2.4-2.8mm long and 0.8-1.0mm wide. The dorsal sepal is 1-3 veined and has an entire margin. The lateral sepals are parallel with the labellum, shaped obliquely elliptic and have acuminate to acute apices. The lateral sepals measure 1.9-2.5mm long and 0.9-1.2mm wide. The lateral sepals are 1-3 veined and have entire margins. The petals are shaped oblong-elliptic to linear-oblong and have obtuse apices. The petals measure 1.7-2.1mm long and 0.5-0.8mm wide. The petals are one veined and have entire margins. The labellum is pendent to somewhat porrect and entire. The labellum is shaped broadly triangular-ovate and has an obtuse often concave apex. The labellum measures 1.3-1.7mm long and 1.1-1.3mm wide. The labellum is three veined and has an entire margin. The labellum can have a few scattered ocelli found around its margin. There is a proximal transverse callus at the base of the labellum. The column is suberect or straight and measures 0.9-1.0mm long. The apical hood is rounded and has an entire to slightly irregular margin. The stelidia grow outwards from the top of the column and are equal to the apical hood. The stelidia are shaped obliquely oblong and have obtuse apices.

 

Herbarium Specimens

 

Holotype

 

AMES

 

Specimen 18827 (photo)

 

 

Isotype

 

Royal Botanic Gardens, Kew (K)

 

I could not locate the specimen

 

 

Other herbarium Specimens

 

National Herbarium Netherlands (L)

 

Specimen L0322640

 

Royal Botanic Gardens, Kew (K)

 

Specimen 38075.000

 

Scent

 

I could find no record.

 

Flowering Season

 

Flowering plants have been from March to May and during July.

 

Culture

 

I know that this species is in cultivation in the USA but have not been able to locate evidence of cultivated specimens anywhere else. The plant was imported from the Philippines under a different name and is now found in a few specialist species collections in the San Francisco area.

 

Similar Species

 

Dendrochilum copelandii

Dendrochilum graciliscapum

 

Other Information

 

Ames wrote "This number proved to be a mixture, several specimens of D. tenue Ames having been mingled with the present species. According to field notes the flowers were purplish red. D. mearnsii is closely related to D. copelandii Ames, from which species it is distinguishable by the callus on the lip, the reduced lateral arms on the column, the one nerved sepals, and its smaller proportions."

 

Henrik Pedersen grouped this species together with Dendrochilum graciliscapum and Dendrochilum copelandii based on the spirally twisted rachis, flowering starting from the distal section of the rachis, entire labellum and relatively wide stelidia. However, Pedersen's revision states that the flowers open from the proximal section of the rachis in this species (Pedersen 1997).

 

Reference -

 

AMES, Oakes. 1908, Illustrations and studies of the Family Orchidaceae Facsimile 2, 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. 08 January 2009. The Board of Trustees of the Royal Botanic Gardens, Kew. Published on the Internet; http://www.kew.org/wcsp/ accessed 08 January 2009.