Accepted name: Dendrochilum karoense J.J.Wood, Lindleyana 7: 74 (1992)

Subgenus – Platyclinis. Section – Eurybrachium.


 
 
 

Synonyms

 

None

 

Origin in the Wild

 

Sumatra

 

Elevation in the Wild

 

1,550 – 1,625 metres

 

Habitat in the Wild

 

This species is endemic to north Sumatra where it grows in lower montane forest on rocks and in exposed positions often in bright light and even full sun. This species has been collected along the Merek to Sidikalang road. The holotype was described as growing on small mossy branches in lower montane forest.

 

The Plants Description

 

The rhizome branches and can measure up to 6cm long. The pseudobulbs cluster close together along the rhizome. The pseudobulbs are shaped ovate and measure 1.2cm long and 0.6cm in diameter. The pseudobulbs are green; Jim Comber wrote that they turn brown in exposed conditions (Comber 2001). The leaves are petiolate, the petiole measures 5-8mm long. The leaf blades are shaped linear-elliptic and have obtuse to minutely apiculate apices. The leaf blades measure 3-4.2cm long and 4-5mm wide.

 

The Inflorescence

 

The peduncle is erect and measures 3.6-4.2cm long. The rachis is erect or arching and measures 2.5-3.2cm long.

 

The Flowers

 

Between 10 and 15 flowers grow on one inflorescence. The flowers are pale pinkish-brown and have a darker brown labellum. The dorsal sepal is shaped oblong-elliptic and has an obtuse apex that is minutely apiculate. The dorsal sepal measures 3.5mm long and 2mm wide. The lateral sepals are nearly the same shape but are oblique and slightly wider. The petals are shaped ovate and measure 3mm long and 2.5mm wide. The petals have erose margins. The labellum is entire and shaped ovate. The base of the labellum is wider than its apex. The lateral margins are erect. The labellum measures 2.8mm long and 2mm wide. There are two keels on the labellum. The column is 0.8mm long. The apical hood has a truncate apex, its margin is indented. The stelidia grow from the base of the column and slightly exceed the column apex. The stelidia are shaped narrowly oblong and have an obtuse apex.

 

Herbarium Specimens

 

Holotype

 

Royal Botanic Gardens Kew (K)

 

Specimen K000078213 (drawing)

Specimen K000078212 (photo)

 

Other herbarium specimens

 

Royal Botanic Gardens Kew (K)

 

Specimen 55378.000

Specimen 61480.00

 

Scent

 

I could find no record.

 

Flowering Season

 

Flowering plants have been collected in the wild during January and October. Jim Comber’s in-situ photograph was taken during October.

 

Culture

 

I do not think this species is in cultivation

 

Similar Species

 

Dendrochilum lamellatum

Dendrochilum carinatum

 

Other Information

 

This species is similar to Dendrochilum lamellatum but differs because it is smaller in all measurements. Dendrochilum karoense has 2 keels not 4 as D. lamellatum does. D. karoense has erose margins and the shape and length of the stelidia differ. This species differs from Dendrochilum carinatum by having 2 keels and obtuse stelidia that grow from the base of the column. Dendrochilum carinatum has stelidia that grow from the top of the column, 4 keels and acute apices on the stelidia.

 

Reference

 

COMBER, J.B. Orchids of Sumatra, 2001, Royal Botanic Gardens Kew

 

World Checklist of Selected Plant Families. 19 October 2008. The Board of Trustees of the Royal Botanic Gardens, Kew. Published on the Internet; http://www.kew.org/wcsp/ accessed 19 October 2008.