Accepted name: Dendrochilum graminifolium (Ames) Pfitzer in H.G.A.Engler (ed.), Pflanzenr., IV, 50 II B 7: 114 (1907)


Subgenus – Acoridium. Section – Acoridium.


 
 

Synonyms

 

Acoridium graminifolium Ames, Proc. Biol. Soc. Wash. 19: 144 (1906).

 

Origin in the Wild

 

Luzon

 

Elevation in the Wild

 

700-2,350 metres

 

Habitat in the Wild

 

The type specimen was collected in 1905 by E.D. Merrill from between Suyoc and Panai in Benguet Province.

 

This Luzon endemic has been recorded from Batangas Province on Mount Makulot; Benguet Province from Mount Data and Mount Pulog; Ifugao Province on Mount Pimmage and Mount Polis; Kalinga-Apayao on Mount Magnus and Mount Duraragan; Mountain Province between Bontoc and Mount Polis.

 

This species usually grows in mossy forest as an epiphyte. A specimen was collected in 20-25m high tall forest on sandy-loamy soil.

 

The Plants Description

 

This Dendrochilum is tufted and grass-like. The pseudobulbs cluster together on a short rhizome and are shaped terete to fusiform. The pseudobulbs measure 3.0-10.4cm long. The pseudobulbs are covered by 4-5 cataphylls while they are growing. The cataphylls disintegrate into persistent fibres as the pseudobulbs mature. The leaves are petiolate; the petiole measures 1.8-9.0cm long. The leaf blades are shaped narrowly linear and have acute apices. The leaf blades measure 15.5-35.3cm long and 0.3-0.4cm wide. The leaves have 3 distinct nerves; the 2 lateral nerves are submarginal.

 

The Inflorescence

 

The peduncle is enclosed for most of its length by the subtending leaf and appears to grow from its distal section. The peduncle measures 9.7-30.5cm long. The rachis measures 4.4-9.1cm long. The flowers alternate distichously and are spaced 1.5-2.0mm apart. There are 1-6 appressed non-floriferous bracts at the base of the rachis. The flowers open from the proximal section of the rachis.

 

The Flowers

 

Ames wrote that the flowers are yellow and turn deep reddish brown if dry (Ames 1906). Henrik Pedersen wrote that the flowers are white to yellow, rarely red or brown, with a deep orange rostellum (Pedersen 1997). The tepals open widely. The dorsal sepal is shaped oblong to lanceolate and has an acuminate apex. The dorsal sepal measures 3.6mm-4.8mm long and 1.1-1.4mm wide. The dorsal sepal has an entire margin is three veined and glabrous. The lateral sepals are shaped ovate-lanceolate and have acuminate apices. The lateral sepals measure 4.4-5.1mm long and 1.6-2.0mm wide. The lateral sepals have entire margins are three veined and glabrous. The petals are shaped elliptic to broadly oblanceolate and are somewhat acuminate at their apices. The petals measure 3.0-4.3mm long and 1.1-1.6mm wide. The petals have entire margins are 3-veined and glabrous. The labellum is porrect, 3-lobed and 1-veined. The side lobes are erect, shaped obliquely oblong and have rounded apices. The side lobes exceed the mid-lobe and are slightly auriculate at their base. The mid lobe is shaped broadly oblong and has a truncate apex, apiculate in its centre. The margins on the labellum are entire. There are 2 lateral calli located at the base of each side lobe. The lateral calli are situated close to the margin. The median callus is located at the proximal centre of the disc.  The column is erect, nearly straight and measures 0.7-0.8mm long. The column is not hooded at its apex. The anther cap is broadly ovate from its upper view and obtuse from the front.

 

Herbarium Specimens

 

Holotype

 

Philippine National Herbarium (PNH)

 

Specimen – destroyed

 

Isotype

 

AMES

 

Specimen 33 (photo)

 

Other herbarium specimens

 

National Herbarium Netherlands, (L)

 

Specimen L0322508

Specimen L0322509

Specimen L0322510

 

Royal Botanic gardens Kew (K)

 

Specimen K000364853

 

AMES

 

Specimen 104047 (photo)

 

Scent

 

Oakes Ames wrote that this species has a scent.

 

Flowering Season

 

Flowering plants have been collected in the wild from September to January and in March.

 

Culture

 

This species is in cultivation and often confused with similar species. Although not commonly offered for sale it often turns up as an unidentified species.

 

Similar Species

 

Dendrochilum tenellum

Dendrochilum perplexum var. montanum (see this page for differences)

Dendrochilum perplexum var. perplexum (see this page for differences)

Dendrochilum stenophyllum

Dendrochilum louisianum

Dendrochilum williamsii

 

Other Information

 

Ames described this species in 1906 as Acoridium graminifolium and said it had an affinity with Acoridium tenellum (Dendrochilum tenellum). Ames wrote that the calli is more like that of Acoridium venustulum (Dendrochilum parvulum) than that of Acoridium tenellum (Dendrochilum tenellum).

 

Henrik Pedersen wrote that this species is allied to Dendrochilum perplexum, D. stenophyllum and D. louisianum. These species are similar because of their dorsiventrally complanate leaves, a peduncle that is adherent to the subtending leaf at the time of flowering and a labellum with a flat or slightly concave disc.

 

Reference

 

AMES, Oakes. 1906, Descriptions of New Species of Acoridium from the Philippines, Proceedings of the Biological Society of Washington, Vol XIX PP. 143-154 September 25, 1906.

 

AMES, Oakes. 1908, Illustrations and studies of the Family Orchidaceae Fascicle 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. 01 November 2008. The Board of Trustees of the Royal Botanic Gardens, Kew. Published on the Internet; http://www.kew.org/wcsp/ accessed 01 November 2008.