Accepted name: Dendrochilum uncatum Rchb.f., Bonplandia (Hannover) 3: 222 (1855).

Subgenus – Platyclinis. Section – Platyclinis.


 
 

Synonyms

 

Dendrochilum cucumerinum Rchb.f., Gard. Chron. 1884(2): 649 (1884).

Acoridium cucumerinum (Rchb.f.) Rolfe, Orchid Rev. 12: 220 (1904).

Platyclinis formosana Schltr., Bull. Herb. Boissier, II, 6: 302 (1906).

Dendrochilum formosanum (Schltr.) Schltr., Repert. Spec. Nov. Regni Veg. Beih. 4: 185 (1919).

Dendrochilum uncatum var. formosanum (Schltr.) T.Hashim., J. Jap. Bot. 57: 26 (1982).

Platyclinis uncata (Rchb.f.) N.E.Br. ex B.S.Williams, Orch.-Grow. Man., ed. 7: 680 (1894).

Acoridium uncatum (Rchb.f.) Rolfe, Orchid Rev. 12: 220 (1904).

 

Origin in the Wild

 

Luzon and Taiwan

 

Elevation in the Wild

 

930-2500 metres (Pedersen)

 

Jim Cootes wrote that this species is found above 500 metres (Cootes 2001).

 

Habitat in the Wild

 

This species has been recorded growing in Bataan Province along the Lamao River in the Mariveles Mountains; Benguet Province at 'Bukod', Mount Pulog and Pauai; Cagayan Province on Mount Balatongan, Mount Bawagan and Mount Cagua; Ifugao Province on Mount Polis and Sumigar; Laguna Province on Mount Maquiling; Pampanga Province on Mount Arayat; Quezon province on Mount Banahao and Rizal Province on Mount Canumay.

 

Ames described this species as growing on rocks and trees.

 

The Plants Description

 

The pseudobulbs cluster along a short rhizome and are shaped fusiform to slenderly obpyriform. The pseudobulbs measure 1.1-4.3cm long and 0.3-0.9cm in diameter. The pseudobulbs are covered by 4-6 cataphylls while they are growing. The cataphylls disintegrate into persistent as the pseudobulbs mature. The leaves are petiolate; the petiole measures 0.4-5.9cm long. The leaf blades are shaped oblanceolate to linear-oblong to linear-lanceolate and abruptly narrow below their apices; the apices are often finely mucronate. The leaf blades measure 12.5-40.2cm long and 2.2-6.4cm wide. The leaves are thin textured and have five distinct nerves.

 

The Inflorescence

 

The inflorescence is synanthous. The peduncle is suberect to curved and measures 5.2-22.5cm long. The rachis is pendent and measures 5.1-14.5cm long. The flowers alternate distichously and are spaced 2.5-5.0mm apart. There are 1-4 appressed non-floriferous bracts at the base of the rachis. The flowers open from the proximal or central section of the rachis.

 

The Flowers

 

The flower is light green to yellow; sometimes the keels and side lobes are a reddish brown colour (Pedersen 1997). Up to 30 flowers can grow on an inflorescence (Cootes 2001). The sepals and petals spread widely. The dorsal sepal is shaped elliptic to linear-lanceolate and has an acute apex which is sometimes finely mucronate. The dorsal sepal measures 3.7-7.8mm long and 1.4-2.9mm wide. The dorsal sepal is three veined (rarely five veined) and has an entire margin. The lateral sepals are shaped ovate to lanceolate-oblong often slightly oblique or falcate and have acute to obtuse apices, sometimes finely mucronate and rarely acuminate. The lateral sepals measure 3.7-7.5mm long and 1.4-3.3mm wide. The lateral sepals are three veined (rarely four veined) and have entire margins. The petals are shaped elliptic and have acute to obtuse apices. The petals measure 3.2-7.1mm long and 1.5-3.4mm wide. The petals are three veined (rarely four veined) and have erose-dentate (rarely quite entire) margins. The labellum is easily versatile, more or less pendent and 3-lobed. The labellum measures 2.5-5.1mm long and 1.2-3.6mm wide. The labellum is three veined and has erose to serrate-fimbriate margins from the base to the apices of the side lobes, the mid-lobe margin is entire. The side lobes are erect, shaped obliquely oblong-triangular and have acuminate-acute apices. The mid-lobe is shaped broadly obcuneate to broadly obovate or suborbicular and has a rounded to subacute apex which is usually apiculate. There are two small keels located on the lateral nerves and which terminate just past the base of the mid-lobe. The column is suberect, somewhat incurved and measures 1.7-2.7mm long. The apical wing is prolonged into a rounded apex with a slightly irregular to few dentate to somewhat erose margin. The apical wing distinctly exceeds the anther cap. The stelidia grow upwards and outwards from the middle of the column and are distinctly shorter than the column apex. The stelidia are incurved, shaped strongly falcate and hook-like with obtuse, rarely acute apices.

 

Herbarium Specimens

 

Holotype

 

Herbarium Reichenbach

 

 

Isotype

 

BM

 

Royal Botanic Gardens, Kew (K)

 

Specimen - I could not locate the specimen

 

National Herbarium Netherlands (L)

 

Specimen L0058492 (photo)

Specimen L0058494 (photo)

 

P

 

W

 

 

Other herbarium specimens

 

Royal Botanic Gardens, Kew (K)

 

Specimen 74831.000 (Dendrochilum formosanum)

Specimen 94594

Specimen 20288

Specimen K000079141 (photo)

Specimen 60107

Specimen 38047

Specimen 36068

Specimen 62371

 

National Herbarium Netherlands (L)

 

Specimen L0322810

Specimen L0322811

Specimen L0322812

 

AMES

 

Specimen 98811 (drawing from the type)

 

Scent

 

Yes, a faint musky scent.

 

Flowering Season

 

Within Taiwan flowering plants have been collected in the wild during November. On Luzon flowering plants have been collected in the wild year round. In cultivation within the northern hemisphere, plants flower from late winter into spring.

 

The flowers last for 10 to 15 days.

 

Culture

 

This species is known in cultivation globally, I have seen plants within the European Union, United States and Australia.

 

Similar Species

 

Dendrochilum parvipapillatum (see this page for the differences)

Dendrochilum amesianum

Dendrochilum gracile

 

Other Information

 

Ames wrote (1908) that Dendrochilum uncatum resembles Dendrochilum longispicatum.

 

Henrik Pedersen studied the holotype of Dendrochilum cucumerinum and could not see any difference to justify it being a separate species, despite Reichenbach's statement that the labellum was different. Pedersen reduced Dendrochilum cucumerinum to a synonym of Dendrochilum uncatum var. uncatum in 1997 (Pedersen 1997)

 

Some botanists have wanted to split the Taiwanese plants into a separate variety, Dendrochilum uncatum var. formosanum, Su wrote in 1988 that there was enough variability in the Taiwanese specimens to warrant a separation from Dendrochilum uncatum var. uncatum. Pedersen followed Su's practice (Pedersen 1997).

 

Henrik Pedersen wrote (1997) that this species only differs from Dendrochilum parvipapillatum by minor characteristics of the leaves, labellum and column.

 

Pedersen's keys to the varieties are:

 

1.       Stelidia appearing from the middle of the column, rarely subbasal (upper margin of the stelidia connected to the column proper approximately at the level of the stigma margin). Fertile stigma linear-oblong to narrowly obtriangular in outline…………………………………………………………………………………………….…………var. uncatum

 

1.       Stelidia basal (the distance between the lower stigma margin and the upper margin of the stelidia at least as long as the stigma itself). Fertile stigma subquadrate to transversely elliptic in outline………………………………………………………var. longispicatum

 

The epithet refers to the incurved stelidia.

 

The provenance of a Leiden specimen from Borneo was called into question by Jeffrey Wood (Wood 2001).

 

Reference -

 

AMES, Oakes. 1908, Illustrations and studies of the Family Orchidaceae Facsimile 2, Ames Botanical Laboratory, North Easton, Massachusetts, Boston.

 

COOTES, Jim. The Orchids of the Philippines, 2001. Timber Press, USA

 

COOTES, Jim. BANKS, David. 1995, The genus Dendrochilum A guide to the species in cultivation, Orchids Australia, AOC

 

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

 

WOOD, Jeffrey. Dendrochilum of Borneo, 2001. Natural History Publications (Borneo), Malaysia.

 

World Checklist of Selected Plant Families. 17 January 2009. The Board of Trustees of the Royal Botanic Gardens, Kew. Published on the Internet; http://www.kew.org/wcsp/ accessed 17 January 2009.