Accepted name: Dendrochilum cruciforme J.J.Wood in J.J.Wood & P.J.Cribb, Check-list Orchids Borneo: 169 (1994)

Subgenus – Platyclinis. Section – Cruciformia.


 
 

Synonyms

 

None

 

Origin in the Wild

 

Sabah

 

Elevation in the Wild

 

900-2000 metres

 

Habitat in the Wild

 

Jeffrey Wood wrote that this species has been collected in the Crocker Range on Mount Alab and Mount Kinabalu. The habitat has been recorded as lower montane forest. This plant has been found as an epiphyte amongst 8m high Leptospermum/Dacrydium growing on east facing slopes on weathered sandstone and shale (Wood 2001).

 

The Plants Description

 

The pseudobulbs cluster on a short rhizome. The pseudobulbs are shaped cylindrical or narrowly fusiform. The pseudobulbs measure 0.5-2.5cm long and 0.2-0.4cm in diameter. The pseudobulbs are covered by 3-4 cataphylls while they are growing. The cataphylls disintegrate into non-persistent fibres as the pseudobulbs mature. The leaves are petiolate; the petiole measures 0.5-2cm long. The leaf blades are shaped narrowly linear and have subacute to acute apices. The leaf blades measure 5-11.5cm long and 0.1-0.3cm wide.

 

The Inflorescence

 

The peduncle is erect and measures 2.5-6.5cm long. The rachis is erect or suberect and measures 3.5-5cm long. The rachis is quadrangular in cross-section. The flowers alternate distichously and are spaced 1-2mm apart. There are no non-floriferous bracts at the base of the rachis.

 

The Flowers

 

The flowers are variable and the following colours have been described, pinkish cream with purple spots, pale yellow, cream-green, cream-yellow, cream or pure white. The labellum generally has a dark coloured blotch at the base of the side lobes and at the apex of the keels. The dorsal sepal is shaped oblong-elliptic and has an acute apex. The dorsal sepal measures 2.2-2.6mm long and 0.6-0.9mm wide. The dorsal sepal has entire margins and is 1-veined. The lateral sepals are shaped ovate-elliptic and have acute apices. The lateral sepals measure 2.1-2.5mm long and 0.8-1mm wide. The lateral sepals have entire margins and are 1-veined. The petals are shaped narrowly elliptic and have acute apices. The petals measure 2.0-2.6mm long and 0.4-0.7mm wide. The petals have entire margins and are 1-veined. The labellum is cruciform and measures 2-2.5mm long and 1.5-2mm at its widest point. The side lobes are shaped triangular, sometime falcate and have acute or subacute apices. The mid-lobe is shaped triangular-acuminate and is cuspidate. The margins on the labellum are entire. There are 2 elevated keels that nearly join at the base of the hypochile and finish before the base of the side lobes. The column is 1-1.2mm long. The apical hood is elongated, has an acute apex with a bidentate or tridentate margin. The stelidia grow from the base of the column are shaped linear-ligulate and have obtuse apices. The stelidia measure 0.9-2mm long. The stelidia are slightly shorter than or equal to the apical hood.

 

Herbarium Specimens

 

Holotype

 

Royal Botanic Gardens Kew (K)

 

Specimen 60406.000

Specimen K000078174 (photo)

Specimen K000078173 (photo)

 

 

Isotype

 

AMES

 

Specimen 112212 (photo)

 

BO

 

E

 

HBG

 

BM

 

G

 

 

Other herbarium specimens

 

Royal Botanic Gardens, Kew (K)

 

Specimen 60405.000

Specimen 56590.000

Specimen 61498.000

Specimen 60407.000

 

National herbarium Netherlands, Leiden (L)

 

Specimen L0322441

Specimen L0322442

Specimen L0322443

 

Scent

 

According to Bacon the flowers have a musky scent.

 

Flowering Season

 

Flowering plants have been collected in the wild during all months except February, April, May and July.

 

Culture

 

I do not think this species is in cultivation.

 

Similar Species

 

Dendrochilum cruciforme var. longicuspe

Dendrochilum hastilobum

Dendrochilum dolichobrachium

Dendrochilum devogelii (see this page for the differences)

Dendrochilum gibbsiae

 

Other Information

 

D. cruciforme var. cruciforme differs from var. longicuspe because the mid lobe is triangular-acuminate and cuspidate rather than long-acuminate. The side lobes on var longicuspe are narrower and the stelidia are longer than the apical hood.

 

This species differs from D. devogelii by the cruciform shaped labellum and shorter stelidia.

 

This species differs from Dendrochilum dolichobrachium but has shorter keels, wider side lobes and a smaller mid-lobe.

 

This species differs from Dendrochilum gibbsiae by its smaller habit, narrower grass-like leaves, three lobed labellum and longer column.

 

The side lobes are variable in shape and size. The apical hood varies from bifid to acute and acuminate but is always longer than the stelidia.

 

The epithet refers to the cross or cruciform shaped labellum.

 

Reference

 

WOOD, Jeffrey. 1997, Orchids of Borneo volume 3. The Sabah Society, Kota Kinabalu, Malaysia.

 

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

 

World Checklist of Selected Plant Families. 15 February 2009. The Board of Trustees of the Royal Botanic Gardens, Kew. Published on the Internet; http://www.kew.org/wcsp/ accessed 15 February 2009.