REDISCOVERY IN SINGAPORE OF VRYDAGZYNEA LANCIFOLIA RIDL. (ORCHIDACEAE)

Abstract

Vrydagzynea lancifolia Ridl. was presumed to be nationally extinct until the rediscovery of a single individual in Bukit Timah Nature Reserve on 29 Oct.2013. Three inflorescences were observed on a single plant, but there was no fruit set. There were no other individuals found in the vicinity. Conservation is necessary to ensure the continued survival of this species in Singapore. A conservation status of critically endangered is proposed for this species.

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NATURE IN SINGAPORE 2014 7: 1–7
Date of Publication: 23 January 2014
© National University of Singapore
REDISCOVERY IN SINGAPORE OF
VRYDAGZYNEA LANCIFOLIA RIDL. (ORCHIDACEAE)
Reuben C. J. Lim1*, Xin Yi Ng, Paul K. F. Leong2, Hubert Kurzweil2, Helena Duistermaat3, Yi Fei Chung4,
Junhao Chen1, Yi Shuen Yeoh5 and Hugh T. W. Tan1
1Department of Biological Sciences, National University of Singapore
14 Science Drive 4, Singapore 117543, Republic of Singapore
2Herbarium, Singapore Botanic Gardens, National Parks Board
1 Cluny Road, Singapore 259569, Republic of Singapore
3Naturalis Biodiversity Center,
P.O.Box 9517, 2300 RA Leiden, The Netherlands
4Central Nature Reserve, National Parks Board
601 Island Club Road, Singapore 578775, Republic of Singapore
5NUS High School of Mathematics and Science
20 Clementi Avenue 1, Singapore 129957, Republic of Singapore
(*Corresponding author: dbsttw@nus.edu.sg)
ABSTRACT. — Vrydagzynea lancifolia Ridl. was presumed to be nationally extinct until the rediscovery of a single
individual in Bukit Timah Nature Reserve on 29 Oct.2013. Three inflorescences were observed on a single plant, but
there was no fruit set. There were no other individuals found in the vicinity. Conservation is necessary to ensure the
continued survival of this species in Singapore. A conservation status of critically endangered is proposed for this
species.
KEY WORDS. — Orchidaceae, Vrydagzynea lancifolia, Singapore, rediscovery
INTRODUCTION
Vrydagzynea Blume of the family Orchidaceae comprises some 40 species distributed from Lower Bengal to Taiwan,
New Guinea, and the Pacific (Seidenfaden & Wood, 1992; Pedersen et. al, 2011). Vrydagzynea is distinguished from
other genera in its subfamily, the Orchidoideae by the presence of stalked glands located within the spur of its lip in the
flower. Three species have been recorded from Singapore—Vrydagzynea albida (Blume) Blume, Vrydagzynea
lancifolia Ridl., and Vrydagzynea tristriata Ridl. These three species were recorded as presumed nationally extinct in
Singapore (Tan et al., 2008; Chong et al., 2009). One plant bearing three inflorescences of Vrydagzynea lancifolia was
recently rediscovered in Bukit Timah Nature Reserve (BTNR), after nearly 80 years of absence (Figs. 1‒7, Table 1).
Description. — This is mostly based on the individual found in Bukit Timah Nature Reserve (BTNR). Vrydagzynea
lancifolia is a terrestrial herb with branched, decumbent, grey-green stems each about 15 cm long with roots arising at
the nodes in the horizontal portion in contact with the ground, ascending to the erect portion bearing about 812 leaves
and terminating in an inflorescence (Fig. 1; Pedersen et. al, 2011). Internodes are about 1.6 cm long near the basal part
of the erect stem portion, reducing to 0.4–0.5 cm long towards the tip, making the spirally arranged, stalked leaves
appear crowded apically. The lanceolate leaf blades are 4.0–6.5 cm long and 1.7–1.8 cm wide, narrowed evenly towards
the acute tip, with sheathed petioles of about 1 cm long. The leaf blades were observed to have slightly undulating
margins and on the upper side, silver-grey longitudinal bands of about 1.0 mm wide on either side of the midrib (Fig. 2).
The upper leaf blade surface is glabrous, while the lower leaf blade surface and the petiole are pilose (Fig. 3). The
terminal inflorescence with more than 40 flowers (Fig. 4A) is 3.0 cm tall and 1.5 cm across, with a peduncle about 0.5
cm long. The inflorescence bracts are green, boat-shaped, and have margins bearing white hairs, sheathed bases, and
acuminate tips. The flowers are resupinate, with the upper ones being held almost vertically. Each flower measures
between 3.5–4.0 mm across, with several opening at a time from the base of the inflorescence upwards. Flowers, when
fresh, have white petals and sepals with brown markings on the dorsal sepal, and all have their white parts maturing to
yellow (Fig. 4B), fading to brown just before abscission. The flowers have narrowly ovate, c. 0.5 mm-long petals, c. 6
mm-long sepals, and an entire lip with a 4.0 mm-long spur. Contained within the lip of the spur at the base is a pair of
stalked glands, each with a stalk 1.5 mm long and 0.8 mm across (Fig. 5) which are characteristics of the genus
(Holttum, 1964; Seidenfaden & Wood, 1992; Keng et al., 1998). The column and rostellum is very short. Capsules are
formed when flowers are pollinated, with the infructescence growing to 6 cm long (Fig. 6).

Lim et al.: Rediscovery of Vrydagzynea lancifolia in Singapore
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Distribution. — Vrydagzynea lancifolia has been recorded in many localities in the understory of lowland forests in
Peninsular Malaysia from Kedah to Johor, as well as in Thailand and Sabah, Borneo (Seidenfaden & Wood, 1992;
Pedersen et. al, 2011). It also occurs in Singapore.
Fig. 1. A, Plant of Vrydagzynea lancifolia in situ in Bukit Timah Nature Reserve. Scale bar = 1cm; B, Decumbent stem (red arrow)
with the two erect inflorescences (Photographs by: Reuben C. J. Lim [A] and Yi Fei Chung [B]).
A
B

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Fig. 2. Upper surface of leaf blades of Vrydagzynea lancifolia
with silver bands along the midrib. Scale bar = 1cm. (Photograph
by: Reuben C. J. Lim).
Fig. 4. A, Inflorescence of Vrydagzynea lancifolia with new and mature flowers showing the brown marking (red arrow) of the dorsal
sepal. Note the fine hairs on the margins of the bracts. Scale bar = 1 cm; B, Close-up of a mature flower. Scale bar = 1 mm.
(Photographs by: Ng Xin Yi).
Fig. 3. Underside of leaves of Vrydagzynea lancifolia and
sheathed petiole with hairs. Scale bar = 1 cm. (Photograph by:
Ng Xin Yi).
A
B

Lim et al.: Rediscovery of Vrydagzynea lancifolia in Singapore
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Fig. 5. Parts of Vrydagzynea lancifolia flower. i, spur of lip; ii, stalked glands; iii,
column; iv, petals; v, dorsal sepal; vi, remaining part of lateral sepal. Scale bar =
0.2 mm. (Photograph by: Paul K. F. Leong & Hubert Kurzweil).
Fig. 7. The habitat of Vrydagzynea lancifolia, on a flat rock covered with leaf litter in the densely shaded, forest understory of Bukit
Timah Nature Reserve. (Photograph by: Reuben C. J. Lim).
Fig. 6. Elongated infructescence of SING
specimen barcode number 0046915, from
Gunung Panti, Malaysia. Scale bar = 1 cm.
(Photograph by: Ng Xin Yi).
vi
i
v
iiii
iv
ii

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Etymology. — Vrydagzynea was named by Carl Ludwig Blume in honour of a Dutch pharmacist, Theodore Daniel
Vrydag Zynen, (Gledhill, 2008). The specific epithet lancifolia is composed of two Latin words, “lancěa” meaning
lance, and “fŏlĭum” meaning leaf, referring to the lance-shaped leaf blade (Marchant & Charles, 1892).
PAST AND PRESENT RECORDS
Vrydagzynea lancifolia was first collected in Singapore in 1889 from Bukit Timah where several subsequent collections
were made by various collectors and it has also been recorded once from Seletar (Table 1).
The Vrydagzynea lancifolia individual with three inflorescences that was rediscovered on 29 Oct.2013 was encountered
as a terrestrial orchid growing on a flat rock on the forest floor (Fig. 7) in the BTNR by HD, YFC, RCJL, JC, and YSY.
It gave the impression of being a Commelinaceae species. The area that the plant grew in was elevated terrain
consisting of leaf litter-covered boulders that were sparsely populated with herbs such as Donax canniformis
(Marantaceae), Zingiber puberulum (Zingiberaceae), and Tectaria singaporiana (Dryopteridaceae) as well as saplings
of climbers that have yet to climb, notably from the Araceae as well as a Pterisanthes species (Vitaceae). The area was
observed to be humid with filtered light under the shade of tall trees. RCJL collected one of the inflorescences and
submitted the fresh specimen to the Herbarium, Singapore Botanic Gardens (SING) for identification. PKFL and HK
confirmed that it was Vrydagzynea lancifolia on 7 Nov.2013 upon dissection of the flowers (Fig. 5), and the specimen
was vouchered (Fig. 8).
On 14 Nov.2013, a team of researchers from SING surveyed the area, but no other individuals were found. The flowers
on the remaining two inflorescences did not show fruit set, and the remaining flowers could not be pollinated in the
field as they were too small. No observation of fruit set was made in the three weeks following the discovery of the
orchid.
Table 1. Previous Singapore collections of Vrydagzynea lancifolia Ridl. deposited in the Herbarium, Singapore Botanic Gardens
(SING).
S/No.
Bar Code No.
Collector
Collector’s No.
Date Collected
Locality
1.
0060106
Anonymous
s.n.
11 Jan.1889
Bukit Timah
2.
0011030
J. S. Goodenough
s.n.
25 Oct.1889
Seletar
3.
0011032
H. N. Ridley
2033
1890
Bukit Timah
4.
0046916
H. N. Ridley
3927
1892
Bukit Timah
5.
0046913
H. N. Ridley
6905
Oct.1895
Bukit Timah
6.
0011031
H. N. Ridley
s.n.
1898
Bukit Timah
7.
0011033
R. E. Holttum
19798
12 Nov.1928
Bukit Timah
8.
0011034
R. E. Holttum
19798
12 Nov.1928
Bukit Timah
9.
0011035
Mohd Nur
24641
26 Feb.1931
Bukit Timah
10.
0163766
Mohd Nur
24641
26 Feb.1931
Bukit Timah
CONCLUSIONS
The BTNR was one of the first areas of tropical forest to be legally protected in Singapore (Corlett, 2011). Despite the
many pressures and disturbances it has undergone, it still supports an immensely rich flora. Although the core area is
quite small at 70 ha, various species thought to be extinct are likely to still persist in this refuge (Turner & Corlett,
1996). The preservation of this area is important, because “In areas with little rain forest remaining, fragments can be
the ‘seeds’ from which to re-establish extensive forest.”—Turner & Corlett (1996). The loss of natural forest habitat,
attributable to widespread land use changes in Singapore, is most likely the cause of the near-extinction of the species
(Corlett, 1991).
In the past, Vrydagzynea lancifolia has been recorded only in two locations in Singapore, Bukit Timah being the most
frequent. As there has only been a single individual of Vrydagzynea lancifolia rediscovered after 80 years of absence in
flower but not fruiting, an extensive survey should be conducted to determine if there are other mature individuals
which can be used for propagation of this species. Given the apparent rarity of the species in Singapore, a conservation
status of nationally critically endangered is proposed in accordance with the criteria of Davison (2008).
While conducting surveys of this species and trying to locate individuals, special attention should be paid to its
unconventional orchid form, as it can be easily mistaken as a member of the Commelinaceae. A conservation plan
based on further study of this species should be established to increase the population size for safeguarding against
stochastic events, such as prolonged drought as experienced in 2005 and 2009, which may wipe out the species.

Lim et al.: Rediscovery of Vrydagzynea lancifolia in Singapore
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Fig. 8. Vouchered specimen of Vrydagzynea lancifolia with SING barcode number 0197737, after its rediscovery. Scale bar = 1 cm.
(Photograph by: Paul K. F. Leong).
ACKNOWLEDGEMENTS
We would like to express our gratitude to the Chief Executive Officer and staff members of the National Parks Board
(NParks) for allowing us access to collections of the Herbarium, Singapore Botanic Gardens (SING), and Bukit Timah
Nature Reserve.
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