Accepted name: Dendrochilum pumilum var. recurvum (Ames) H.A.Pedersen, Opera Bot. 130: 24 (1997)

Subgenus – Acoridium. Section – Convoluta.


 
 

Synonyms

 

Acoridium recurvum Ames, Proc. Biol. Soc. Wash. 19: 148 (1906).

Dendrochilum recurvum (Ames) Ames, Philipp. J. Sci., C 2: 318 (1907).

 

Origin in the Wild

 

Luzon, Mindoro and possibly Mindanao

 

Elevation in the Wild

 

700-2795 metres

2,500 metres (Mount Data)

 

Habitat in the Wild

 

Collected on Luzon on Mount Data, the Mayon Volcano, Mount Pulogloco, Mount Pico de Loro, Mount Duraragan, Mount Magnas and Mount Pukis. This species was collected on Mindoro on Mount Halcon (Ames 1907). On Mindanao this species has been collected on Mount Kampalili, Pederson wrote that the Mindanao identifications remain uncertain (Pedersen 1997).

 

Ames wrote that this species was collected by E.D. Merrill on Mount Halcon in ridge forest.

 

Henrik Pedersen wrote (1997) that this species grows as an epiphyte in mossy forest and on exposed ridges.

 

The Plants Description

 

The pseudobulbs are spaced c2cm apart on an elongated rhizome and are shaped fusiform-terete. The pseudobulbs measure 1.7-7.0cm long and 0.2-0.7cm diameter. The pseudobulbs are covered by 5-6 cataphylls while they are growing. The cataphylls soon disintegrate into non-persistent fibres as the pseudobulbs mature. The leaves are petiolate; the petiole measures 0.5-2.8cm long. The leaf blades are shaped linear-lanceolate and have acute to obtuse apices that are sometimes finely mucronate. The leaf blades measure 4.0-15.2cm long and 0.6-1.9cm wide. The leaves have 3-5 distinct nerves on the blade; the two outermost nerves are 1.0-3.0mm from the leaf margin.

 

The Inflorescence

 

The inflorescence is synanthous. The peduncle is suberect to somewhat curved and measures 1.4-14.1cm long. The rachis is nodding and measures 3.0-7.3cm long. The flowers alternate distichously and are spaced 2.0-3.5mm apart. There are 1-3 appressed non-floriferous bracts at the base of the rachis. The flowers open from the distal section of the rachis.

 

The Flowers

 

Ames wrote that an average of 10-13 flowers grow on an inflorescence (Ames 1908), Pedersen wrote that 11+ flowers grow on an inflorescence (Pedersen 1997). The flowers are yellow to yellow-green. The sepals and petals spread widely. The dorsal sepal is shaped elliptic-oblong and has a subacute to rounded apex. The dorsal sepal measures 3.5-4.7mm long and 1.5-2.1mm wide. The dorsal sepal is three veined and has an entire margin. The lateral sepals are shaped obliquely ovate and have obtuse apices that are sometimes finely mucronate. The lateral sepals measure 3.5-4.1mm long and 2.0-2.6mm wide. The lateral sepals are three veined and have entire margins. The petals are shaped obovate and have acute to rounded-obtuse apices. The petals measure 3.1-4.1mm long and 2.2-2.7mm wide. The petals are three veined and have entire margins. The labellum is porrect and 3-lobed. The labellum measures 1.1-1.7mm long and 1.8-2.7mm wide. The labellum is three veined, glabrous and has entire margins. The side lobes are erect, shaped falcately-oblong and have rounded-obtuse apices. The side lobes equal or slightly exceed the mid-lobe. The mid-lobe is shaped transversely oblong and has a rounded-truncate apex that is apiculate in its centre. There are three calli, the lateral calli are rounded, minute and located at the base of each side lobe. The median callus is shaped oblongoid and is located at the centre of the hypochile. The column is suberect and measures 0.6-1.0mm long. The column is hooded at its apex, oblong from the front view and somewhat emarginate from the front. Stelidia and column foot are absent.

 

Herbarium Specimens

 

Holotype

 

Philippine National Herbarium, (PNH)

 

Specimen - destroyed

 

 

Isotype

 

AMES

 

Specimen 50 (photo)

 

Royal Botanic Gardens, Kew (K)

 

I could not locate the specimen

 

 

Other herbarium specimens

 

National Herbarium Netherlands (L)

 

Specimen L0322714

 

Scent

 

I could find no record.

 

Flowering Season

 

Flowering plants have been collected in the wild during June, September and November. Pederson wrote (1997) that a plant flowered in cultivation during February, I could not find in which hemisphere this was.

 

Culture

 

I have heard that this species is in cultivation but have never seen a correctly identified plant. Pedersen wrote (1997) that a cultivated plant flowered during February.

 

Similar Species

 

Dendrochilum irigense (see this page for differences)

Dendrochilum exile

Dendrochilum mindorense

Dendrochilum pumilum var pumilum

Dendrochilum tenuibulbum

Dendrochilum longibulbum

Dendrochilum schweinfurthianum

 

Other Information

 

Ames wrote in 1908 that Dendrochilum recurvum is nearly allied to Dendrochilum pumilum but with a larger and different growth habit. Ames also mentioned that Dendrochilum recurvum is different from all other Philippine Dendrochilum because of its recurved pseudobulbs that grow from a branched rhizome, the cataphylls are spotted and cover the pseudobulbs and petiole. L.O. Williams agreed with Ames and wrote (1951) that this species can be distinguished by the smaller flowers, larger leaves. Henrik Pedersen, in 1995, placed Dendrochilum recurvum as a variety of Dendrochilum pumilum.

 

A copy of Henrik Pedersen key to the two Dendrochilum pumilum varieties are as follows:

 

1.    Pseudobulbs clustered on a short rhizome. Rachis 7-13 flowered. Petals 4.0-6.2mm long…………………………………………………………………………………. var pumilum

2.    Pseudobulbs placed up to c2cm apart on a somewhat elongate rhizome. Rachis 11 to many flowered. Petals 3.90-4.1cm long ………………………….. var recurvum

 

I have relied on the description provided by Pedersen rather than Ames because more plants have been collected since Ames original description.

 

Reference -

 

AMES, Oakes. 1907, Orchidaceae Halconenses: An Enumeration of the Orchids Collected on and Near Mount Halcon, Mindoro, Chiefly By E.D. Merrill, Bureau of Printing, Manila.

 

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. 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.