Accepted name: Dendrochilum mucronatum J.J.Sm., Brittonia 1: 106 (1931)



Subgenus – Platyclinis. Section – Platyclinis.


 
 

Synonyms

 

None

 

Origin in the Wild

 

Kalimantan Timur, Sarawak

 

Elevation in the Wild

 

1200-1800 metres

 

Habitat in the Wild

 

Within Sarawak this species has been collected on Mount Pueh and Mount Rumput both in the Lundu District.

 

Within Kalimantan this species has been collected once on Mount Sungai Pendan in Kalimantan Timur.

 

The habitat is upper montane mossy forest.

 

The Plants Description

 

The pseudobulbs cluster together on a branching rhizome that can grow to 10cm long. The pseudobulbs are positioned at an acute angle to the rhizome, shaped oblong-ovoid and measure 1.0-1.6cm long and 0.6-0.8cm in diameter. The pseudobulbs are covered by 3-4 cataphylls while they are growing. The cataphylls disintegrate into fibres as the pseudobulbs mature. The leaves are petiolate; the petiole measures 2.3-3.0cm long. The leaf blades are shaped linear, ligulate and have acute and mucronate apices. The blades measure 7.0-18.0cm long and 0.25-4.0cm wide. The blades are rigid, coriaceous and have 3-5 distinct nerves along their length.

 

The Inflorescence

 

The inflorescence is synanthous. The peduncle is erect to gently curved and measures 5.5-8.0cm long. The rachis is gently curved and measures 9.0-16.5cm long. The rachis is quadrangular in cross-section. The flowers alternate distichously and are spaced 2.0-2.5mm apart. There are none or one non floriferous bract at the base of the rachis.

 

The Flowers

 

The flowers are a cream flushed with green colour (Wood 2001). The sepals and petals spread widely. The dorsal sepal is shaped narrowly elliptic and has an acuminate apex. The dorsal sepal is concave basally and reflexed towards its apex. The dorsal sepal measures 5.4-5.5mm long and 1.2-1.3mm wide. The dorsal sepal is three veined and has an entire margin. The lateral sepals are shaped obliquely obovate-elliptic and have acuminate or acute apices. The lateral sepals measure 5.3-5.4mm long and 1.5mm wide. The lateral sepals are three veined and have entire margins. The petals are shaped narrowly linear-elliptic and have acute apices. The petals measure 5.0mm long and 1.0mm wide. The petals are three veined, narrowed basally and have minutely erose margins. The labellum is stipitate to the column foot by a short claw, recurved, three veined and 3-lobed. The labellum measures 4.0mm long. The side lobes are flat, shaped narrowly triangular and have acute apices. The side lobes margins are minutely serrate to erose. The mid-lobe is shaped obovate and has a triangular shaped, acute apex. The mid-lobe has an irregular to almost erose margin. There are two prominent keels that are joined at the base. The keels terminate before the middle of the mid-lobe. There is an elevated median nerve that joins the two keels basally and forms an M shape. The column is gently incurved and measures 2.5mm long. The column foot is short. The apical hood is elongated, shaped subquadrate and has a truncate apex with irregularly toothed margins. The stelidia grow upwards from the middle of the column and slightly exceed the column apex. The stelidia are shaped obliquely narrowly elliptic and have subacute apices.

 

Herbarium Specimens

 

Holotype*

 

New York Botanical garden (NY)

 

Specimen 8743 (photo)

 

National Herbarium Netherlands (L)

 

 

Isotype

 

AMES

 

Specimen 61168 (photo)

 

BO

 

Royal Botanic Gardens, Kew (K)

 

Specimen K000079128 (photo)

 

SAR

 

SING

 

National Herbarium Netherlands (L)

 

Specimen L0056512

 

 

Other herbarium specimens

 

National Herbarium Netherlands (L)

 

Specimen L0269662

 

SING

 

Royal Botanic Gardens, Kew (K)

 

Specimen 60721.000

Specimen 60722.000

 

SAR

 

AMES

 

Scent

 

I could find no record.

 

Flowering Season

 

Flowering plants have been collected in the wild during August, September and October.

 

Culture

 

I do not think this species is in cultivation

 

Similar Species

 

Dendrochilum quisumbingianum (see this page for the differences)

Dendrochilum tenuitepalum (see this page for the differences)

 

Other Information

 

* Leiden and New York herbarium both claim to have the holotype. I have added them both in under holotype as I am unsure which is correct.

 

The plant found in Kalimantan differs in having more distinct side lobes, serrate margins on the side lobes and sometimes with extrorse teeth at the base of the keels (Wood 2001).

 

The epithet refers to the sharp pointed habit of the leaves, sepals, petals and labellum.

 

Reference

 

BEAMAN, Teofila, WOOD, Jeffrey, BEAMAN, Reed, BEAMAN, John. 2001, Orchids of Sarawak, Natural History Publications Borneo, Kota Kinabalu, Malaysia.

 

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

 

World Checklist of Selected Plant Families. 23 July 2009. The Board of Trustees of the Royal Botanic Gardens, Kew. Published on the Internet; http://www.kew.org/wcsp/ accessed 23 July 2009.