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Orchids in Assam, India: The Genus DENDROBIUM Swartz
Khyanjeet Gogoi¹, Raju Das², Samuel Rai³ and Rajendra Yonzone4
¹The Orchid Society of Eastern Himalaya, Regional Orchid Germplasm
Conservation & Propagation Centre (Assam Circle)
Daisa Bordoloi Nagar, Talap, Tinsukia- 786156, Assam, India
²Nature’s Foster, P. Box 41, Shastri Road, P.O. Bongaigaon, 783380, Assam,
India
³Cinchona and Other Medicinal Plants, Mungpoo, Darjeeling, W. B., India 4Dept. of Botany, St. Joseph's College, P.O. North Point -734104, District Darjee-
ling, W. B., India
¹Corresponding author e-mail: [email protected]
ABSTRACT
Assam, the second largest state of North-East India, is a treasure trove of or-
chids. In an orchid flora of Assam 53 species of Dendrobium were recorded during
an intensive survey during 1996-2012. The present paper deals with Dendrobium
species diversity and distribution in Assam. This attempt is the first step to correct
taxonomic identifications; to work out currently accepted botanical names with
flowering periods, habitats, and the distribution of the genus Dendrobium within
this area. This paper also briefly describes and illustrates different species of Den-
drobium available in Assam.
Key words: Orchid, Dendrobium, Assam, Enumeration.
INTRODUCTION In terms of the number of species, the orchid family is the largest of the angio-
sperm flora. In India it is mainly distributed in the Eastern Himalayas along with
the country’s northeastern region. A huge number of orchids are found in India,
and this numerical strength in terms of species varies from 800 to 1500, making
India one of the richest orchid floras in tropical Asia (Kumar and Manilal, 1990;
Dressler, 1981; Santapau and Henry, 1973). In the recent past, from statistical
analyses of the angiospermic flora, it has been revealed that the orchid family,
with 184 genera and 1,331 species, forms the largest order of flowering plants in
Eastern Himalayas (Misra, 2007). The Assam region is one of the major habitats
of Dendrobium in the world and the centre of species diversity of one of the im-
portant and interesting epiphytic groups of orchids known for their beautiful and
long-lasting flowers of diverse morphological features.
Dendrobium Sw. is one of the three largest orchid genera containing approxi-
mately 1197 species (Cribb & Govaerts, 2005) as well as one of the most im-
portant genera in commercial horticulture. The genus Dendrobium was established
in 1799 by O. Swartz in Nova Acta Regiae Societatis Scientiarum Upsalieniss
(Chen et al., 2009) and is widely distributed throughout India across to Japan,
The MIOS Journal 15(8): 5-24. 2014. Gogoi, K. et al. Orchids in Assam, India: The Genus Dendrob...
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south to Malaysia and Indonesia, east to Australia, New Guinea, and the Pacific
islands (Chen et al., 2009). In India, it is the second largest genus among the orchi-
daceae and is represented by 103 species distributed in the Eastern Himalayas,
Western Himalayas, Western Peninsular area, and Andaman and Nicobar Island
(Misra, 2007) out of which 77 species are from northeast region (Singh et al.,
2001) and nearly 53 species grow in Assam. Dendrobium assamicum Chowdhury
was reported from Assam in 1988 and it has been already declared as extinct due
to habitat destruction.
There are few comprehensive accounts on Dendrobium, therefore, a survey on
biodiversity of Dendrobium, its distribution and its present status has been done
for the study and assessment of its present status in Assam.
Study Area
Assam bears a separate identity phytogeographically and represents different
types of plant communities. It extends between the latitudes of 24°8’ N - 28°2’ N
and longitudes of 89°42’ E - 96° E. The T-shaped state is sprawled in an area of
78,438 km². It is bordered by the Indian states of Arunachal Pradesh, Nagaland,
Manipur, Mizoram, Tripura, Meghalaya, and West Bengal. Assam shares its inter-
national borders with Bhutan and Bangladesh. Assam is to be found in the central
part of North-East India. It is connected to the rest of the country through a narrow
strip known as Chicken’s Neck in West Bengal. Its unique ecosystem favors luxu-
riant growth of plants considered as Natures reservoir of plants resources. Almost
all varieties of plants relating to different climatic conditions are found in the state
where orchids are a major component of vegetation.
According to the State of Forest Report 1997 of Forest Survey of India, the for-
est cover of Assam, excluding grasslands stands at 24,459 sq. km. Owing to the
location in the sub-tropical zone and the prevalence of the Monsoon climate; the
landmass of Assam possesses mainly evergreen, semi-evergreen and deciduous
trees. However, depending upon the intensity of precipitation, humidity and tem-
perature, the forests are classified as wet or dry. Variation occurs in growth of dif-
ferent species of trees in different parts of the state due to different soil and ground
water regimes and other geographical factors. The general trend of change in the
forest type on the basis of predominant plant species from Western Assam to the
East is moist deciduous, semi-evergreen, evergreen and rain forest respectively.
The vegetation cover found in Assam can be classified as- Evergreen/semi-
evergreen Forest 9797.69 sq. km; deciduous forest 4537.33 sq. km.; Degraded
Forest 2137.64 sq. km.; and Grassland 2369.18-19631. 85 sq. km.
Climate
The climate of Assam is typically ‘tropical monsoon rainfall’ type, with a high
level of humidity and heavy rainfall. Since the state of Assam is known to have
maximum amount of rainfall, the temperatures never go beyond the standard 350 C
to 380 C. It has a moderate climate with warm summers and mild winters. In the
monsoon season, the whole state comes alive with the beauty of nature. Climatic
variations can be seen regionally. On the one hand, the hilly regions of Assam
experience a suitable sub-alpine climatic condition while on the other hand, the
The MIOS Journal 15(8): 5-24. 2014. Gogoi, K. et al. Orchids in Assam, India: The Genus Dendrob...
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plain lands of the state go through excessively humid weather.
There are four distinct seasons in Assam - summer, monsoon, autumn and win-
ter.
Summers: The summer season in Assam starts from the month of March and
extends till the end of June. The season is characterized by extreme humidity and
frequent showers. The average temperature during this time of the year is between
35o and 38o C.
Monsoons: This season brings relief from the scorching heat of the summers.
The average annual rainfall in the state is around 70 inches in the West and around
120 inches in the East.
Winters: The winter season in Assam is basically characterized by scanty rainfall
and misty mornings and afternoons. It starts in November and continues till the
month of February. The average temperature during this time of the year is around
6o to 8o C.
Spring and Autumn: In Assam, in the spring (March-April) and autumn
(September-October) seasons, receives moderate temperature and rainfall, and is
neither too cold nor too hot.
MATERIALS AND METHODS
The intensive field survey work was carried out during 2006- 2012 and covered
all the seasons of the year in all parts of the forest areas of Assam. Collected orchid
specimens along with Dendrobium species were made into standard mounted her-
barium sheets following the procedure of Jain and Roa, 1977. The authors have
done photographs and sketches of orchid species available from the region. The
specimens were identified, described, and nomenclature checked with the help of
the literatures of Hooker, 1890; King and Pantling, 1898; Seidenfaden, 1962; Deva
& Nathani, 1968; Deorani & Nathani., 1995; Chen et al., 2009; Pradhan, 1979;
Pearce and Cribb, 2002; Mishra, 2007; Lucksom, 2007; Chowdhery, 1998, and
specimens authentication was done in the herbarium of the Department of Botany,
Guwahati University and BSI Shillong (Assam herbarium).
Taxonomic studies
Dendrobium Swartz belongs in subfamily: Epidendroideae; tribe: Dendrobieae,
and subtribe: Dendrobiinae. Fifty three species of Dendrobium were recorded from
the Assam, namely, D. acinaciforme Roxb., D. aduncum Lindl., D. amoenum Wall.
ex Lindl., D. amplum Lindl., D. anceps Sw., D. angulatum Lindl., D. aphyllum
(Roxb.) C.E.C.Fisch., Dendrobium assamicum S.Chowdhury, D. bensoniae
Rchb.f., D. bicameratum Lindl., D. chrysanthum Wall. ex Lindl., D. chryseum
Rolfe, D. chrysotoxum Lindl., D. crepidatum Lindl. & Paxton, D. cumulatum
Lindl., D. darjeelingense Pradhan, D. densiflorum Lindl., D. devonianum Paxton,
D. eriiflorum Griff., D. falconeri Hook., D. farmeri Paxton, D. fimbriatum Hook.,
D. formosum Roxb. ex Lindl., D. fugax Rchb.f., D. gibsonii Paxton, D. griffithi-
anum Lindl., D. heterocarpum Wall. ex Lindl., D. hookerianum Lindl., D. jenkinsii
Wall. ex Lindl., D. keithii Ridl., D. kentrophyllum Hook.f., D. lindleyi Steud., D.
lituiflorum Lindl., D. mannii Ridl., D. moniliforme (L.) Sw., D. moschatum (Buch.-
Ham.) Sw., D. nathanielis Rchb.f., D. nobile Lindl., D. pachyphyllum (Kuntze)
The MIOS Journal 15(8): 5-24. 2014. Gogoi, K. et al. Orchids in Assam, India: The Genus Dendrob...
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Bakh.f., D. palpebrae Lindl., D. parciflorum Rchb.f. ex Lindl., D. parishii Rchb.f.,
D. polyanthum Wall. ex Lindl., D. praecinctum Rchb.f., D. pulchellum Roxb. ex
Lindl., D. ruckeri Lindl., D. salaccense (Blume) Lindl., D. spatella Rchb.f., D.
stuposum Lindl., D. sulcatum Lindl., D. terminale C.S.P. Parish & Rchb.f., D.
transparens Wall. ex Lindl., D. wardianum R.Warner, D. williamsonii Day &
Rchb.f. Out of these, 3 species, namely, D. keithii, D. graffithianum, D. pachy-
phyllum are endemic to the state. Most of the species were reported by earlier
workers. All species were found in epiphytic conditions, except D. moschatum
which was also found occasionally in lithophytic conditions (Figs. 1-4).
The MIOS Journal 15(8): 5-24. 2014. Gogoi, K. et al. Orchids in Assam, India: The Genus Dendrob...
Fig. 1. Figures of flowers, intact.
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The MIOS Journal 15(8): 5-24. 2014. Gogoi, K. et al. Orchids in Assam, India: The Genus Dendrob...
Fig. 2. Figures of flowers, perigynous images.
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The MIOS Journal 15(8): 5-24. 2014. Gogoi, K. et al. Orchids in Assam, India: The Genus Dendrob...
Fig. 3. Figures of flowers, labella.
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The MIOS Journal 15(8): 5-24. 2014. Gogoi, K. et al. Orchids in Assam, India: The Genus Dendrob...
Fig. 4. Figures of flowers, column with ovary.
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RESULTS AND ENUMERATION OF SPECIES
Dendrobium acinaciforme Roxb., F l. Ind. ed. 1832, 3: 487 (1832); Hook. f., F l.
Brit. Ind. 5: 723 (1890); Pradhan, Indian Orchid-II, 344 (1979); Barua, Orch. Fl.
Kamrup dist. 151 (2001); Chowdhry, Orch. Fl. Arunachal Prad., 283 (1998); Mish-
ra, Orch. India, 291 (2007). [Fig. 5]
Dendrobium scalpelliforme Teijsm.
& Binn., Natuurk. Tijdschr. Ned.-
Indië 27: 17 (1864).
Stem 10–30 cm long, compressed;
leaves 3.5–5 × 0.6–0.8 cm, lanceo-
late, distichous, fleshy; inflo-
rescence racemose, flowers solitary,
yellowish-white, small, about 1cm.
long.
Flowering: June – August.
Habitat: Epiphyte on tree trunk in
dense humid evergreen forest.
Distribution: India, China, Thai-
land, Cambodia, Vietnam and Ma-
laysia.
Dendrobium aduncum Lindl., Edwards's Bot. Reg. 28 (Misc.): 58 (1842); Hook.
f., Fl. Brit. Ind. 5: 730 (1890); Pradhan Ind. Orchid-II, 324 (1979); Chowdhry,
Orch. Fl. Arunachal Prad., 283 (1998); Mishra, Orch. India, 291 (2007). [Fig. 6]
Dendrobium aduncum var. faulhaberianum (Schltr.) Tang & Wang, Acta Phytotax.
Sin. 1: 80 (1951).
Plant pendulous. Pseudobulbs, cy-
lindric, 50–100 cm, with many
nodes. Leaves many , oblong or
narrowly elliptic, 5–7.5 × 1–1.8 cm,
, linear lanceolate, acute acuminate.
Inflorescences often several, zigzag,
each racems of 4–9 flowers. Flow-
ers 1.2–2 cm across, pale purple;
sepals and petals pale pink, lip
white, callus green, column white,
anther cap deep purple.
Flowering: May- June.
Habitat: Epiphyte on a small tree
trunk in dense humid evergreen
forest,
Distribution: N.E. India, Bhutan,
Burma, China, Thailand, Vietnam.
The MIOS Journal 15(8): 5-24. 2014. Gogoi, K. et al. Orchids in Assam, India: The Genus Dendrob...
Fig. 5. Dendrobium acinaciforme Roxb., 1832.
Fig. 6. Dendrobium aduncum Lindl., 1842.
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Dendrobium amoenum Wall. ex Lindl., Gen. Sp. Orchid. Pl.: 78 (1830); Hook.
f., Fl. Brit. Ind. 5: 738 (1890); Pradhan, Indian Orchid-II, 315 (1979); Chowdhry,
Orch. Fl. Arunachal Prad., 283 (1998); Mishra, Orch. India, 291 (2007). [Fig. 7]
Callista amoena (Wall. ex Lindl.) Kuntze, Revis. Gen. Pl. 2: 654 (1891).
Dendrobium egertoniae Lindl., Edwards's Bot. Reg. 33: t. 36 (1847).
Dendrobium mesochlorum Lindl., Edwards's Bot. Reg. 33: t. 36 (1847).
Epiphytic or lithophytic. Stem 30–
75 cm long, slender, slightly
thickened at nodes, pendulous.
Leaves 5–12 × 0.7–2.2 cm, ob-
long- oblanceolate, acute. Inflo-
rescence many, 0.3–3 cm long,
fasciculate, from nodes of leafless
stem. Flowers 3–4.2 cm across,
white with sepals and petals
tipped with purple, fragrant.
Flowering: May- June.
Habitat: Epiphyte on a small tree
trunk in dense humid evergreen
forest,
Distribution: India, Bhutan and
Nepal.
Dendrobium amplum Lindl. in N. Wallich, Pl. Asiat. Rar. 1: 25 (1830); Hook. f.,
Fl. Brit. Ind. 5: 711 (1890). [Fig. 8]
Epigeneium amplum (Lindl.) Sum-
merh., Kew Bull. 12: 260 (1957).
Pseudobulbs ovoid or elliptic, 20–
50 × 7–20 mm, 2-leaved, enclosed
in membranous sheaths. Leaf ellip-
tic or oblongelliptic, 6–22.5 × 5.5
cm, leathery. Inflorescence much
shorter than leaves, 1-flowered.
Flowers spreading, yellowish
green, spotted with deep brown,
large.
Flowering: November.
Habitat: Growing Lithophytic on
rocks or epiphytic on tree trunks in
forests or along streams.
Distribution: China, Bhutan, NE
India, Myanmar, Nepal, Thailand,
Vietnam.
The MIOS Journal 15(8): 5-24. 2014. Gogoi, K. et al. Orchids in Assam, India: The Genus Dendrob...
Fig. 7. Dendrobium amoenum Wall. ex Lindl., 1830.
Fig. 8. Dendrobium amplum Lindl., 1830.
14
Dendrobium anceps Sw., Kongl. Vetensk. Acad. Nya Handl. 21: 246 (1800);
Hook. f., Fl. Brit. Ind. 5: 724 (1890); Pradhan, Indian Orchid-II, 344 (1979);
Chowdhry, Orch. Fl. Arunachal Prad. 287 (1998); Barua , Orch. Fl. Kamrup dist.
154 (2001); Mishra, Orch. India, 292 (2007). [Fig. 9]
Aporum anceps (Sw.) Lindl., Gen.
Sp. Orchid. Pl.: 71 (1830).
Ditulima anceps (Sw.) Raf., Fl.
Tellur. 4: 41 (1838).
Plants small to large sized, pendu-
lous. Stem flattened, zigzag, upto
50 cm long. Leaf 2.5–4.5×0.6–1.3
cm, many, fleshy, deciduous, disti-
chous, ovate-lanceolate, acute.
Inflorescence short, terminal and
lateral. Flowers yellowish-green,
small, single, fleshy, fragrant, aris-
ing from in between the leaf axils.
Flowering: April-July.
Habitat: Growing Lithophytic on
rocks or epiphytic on tree trunks in
tropical and subtropical valleys.
Distribution: India, Bangladesh,
Nepal, Bhutan, Andaman Islands,
Myanamar, Thailand, Laos, Cambodia and Vietnam.
Dendrobium angulatum Lindl., Gen. Sp. Orchid. Pl.: 88 (1830); Mishra, Orch.
India, 292 (2007).
Dendrobium podagraria Hook.f., Fl. Brit. India 5: 728 (1890), nom. illeg.
Dendrobium inconcinnum Ridl., J. Linn. Soc., Bot. 32: 255 (1896).
Plants small to medium sized. Stem slender, lightly swollen above the base. Leaf 3
–12, linear to oblong, widely spaced. Inflorescence short, arising from the upper
nodes. Flower solitary, white with yellow.
Flowering: April-May.
Habitat: Epiphytic on tree trunks in tropical and subtropical forest.
Distribution: India (Assam), Bangladesh, Burma, southwestern Thailand and Vi-
etnam.
Dendrobium aphyllum (Roxb) Fisher, in Gamble, F l. Press. Madras 3: 1416
(1928); Hook. f., Fl. Brit. Ind. 5: 738 (1890); Chowdhry, Orch. Fl. Arunachal Prad.
287 (1998); Pradhan, Ind. Orchid-II, 321 (1979); Barua, Orch. fl. Kamrup Dist;
169 (2001); Mishra, Orch. India, 292 (2007). [Fig. 10]
Dendrobium cucullatum R.Br., Bot. Reg. 7: t. 548 (1821).
Dendrobium pierardii Roxb. ex Hook., Exot. Fl. 1: t. 9 (1822).
Plans with pseudobulbs, 60–120 cm long, pendulous, leafless when flowering.
Leaves deciduous, sessile, sheathing, internode 3–4 cm. Flowers 1–3 each node,
pale rose, 4.5–5 cm across; lip pubscent, orbicular at the base, shortly convolute-
The MIOS Journal 15(8): 5-24. 2014. Gogoi, K. et al. Orchids in Assam, India: The Genus Dendrob...
Fig. 9. Dendrobium anceps Sw., 1800.
15
ciliate, pale yellow with radiating streaks at the base.
Flowering: April – May.
Habitat: Epiphyte in mixed
deciduous forest or open
forest.
Distribution: India, Nepal,
Bhutan, Burma, China,
Thailand, Cambodia, Vi-
etnam, Peninsular Malaysia.
Dendrobium bensoniae
Rchb.f., Bot. Zeitung
(Berlin) 25: 230 (1867);
Hook. f., Fl. Brit. Ind. 5:
739 (1890); Pradhan, Indian
Orchid-II, 314 (1979);
Mishra, Orch. India, 292
(2007).
Callista bensoniae (Rchb.f.)
Kuntze, Revis. Gen. Pl. 2:
654 (1891).
Pseudobulb yellow, fleshy,
erect or pendulous, cylindrical, 30–75 cm long. Leaves linear, lanceolate or oval,
leathery, deciduous, 5 cm long. Inflorescences 1 or 2 arising from the upper nodes
of leafless stems, 1–3 flowered, racemose. Flowers 5–6 cm across, fragrant, sepals
and petals white or cream, lip white with orange disk and two dark large black-
purple spots at the base, orbicular,
tomentose.
Flowering: April-May.
Habitat: Epiphytic on tree trunks
in lowland and sub-montane
moist forests.
Distribution: NE India, Burma
and possibly Thailand.
Dendrobium bicameratum Lindl., Edwards's Bot. Reg. 25
(Misc.): 59 (1839); Hook. f., Fl.
Brit. Ind. 5: 729 (1890); Chow-
dhry, Orch. Fl. Arunachal Prad.,
287 (1998); Pradhan, Indian Or-
chid-II, 323 (1979); Mishra,
Orch. India, 292 (2007). [Fig. 11]
Callista bicamerata (Lindl.)
Kuntze, Revis. Gen. Pl. 2: 654
(1891).
The MIOS Journal 15(8): 5-24. 2014. Gogoi, K. et al. Orchids in Assam, India: The Genus Dendrob...
Fig. 10. Dendrobium aphyllum (Roxb) Fisher, 1928.
Fig. 11. Dendrobium bicameratum Lindl., 1839.
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Dendrobium breviflorum Lindl., J. Proc. Linn. Soc., Bot. 3: 14 (1858).
Pseudobulb 8.5–23.5 cm long, fusiform, curved. Leaves 4–6, alternate, elliptic-
lanceolate, acute, usually 6.5–10.2 × 1.2–1.5 cm. Inflorescences 1–2, 1.4 cm long,
2–5 flowered, arising from the nodes. Flowers 1–1.2 cm across, pale yellow to
pale green striped with purplish pink to red, lip pale yellow at base.
Flowering: July-August
Habitat: Epiphytic on tree trunks in temperate forests.
Distribution: Himalayas Bangladesh, Assam, India, Nepal, Myanamar and Thai-
land.
Dendrobium chrysanthum Wall. ex Lindl., Edwards's Bot. Reg. 15: t. 1299
(1830); Hook. f., Fl. Brit. Ind. 5: 747 (1890); Chowdhry, Orch. Fl. Arunachal
Prad., 290 (1998); Pradhan, Indian Orchid-II, 322 (1979); Mishra, Orch. India, 292
(2007). [Fig. 12]
Callista chrysantha (Wall.
ex Lindl.) Kuntze, Revis.
Gen. Pl. 2: 654 (1891).
Dendrobium paxtonii
Lindl., Edwards's Bot. Reg.
25(Misc.): 43 (1839).
Stems pendulous or curv-
ing, cylindric, 50–200 cm,
stout, fleshy. Leaves oblong
-lanceolate, usually 13–19
× 1.5–4.5 cm, papery, acu-
minate. Inflorescences leaf-
opposed, lateral, 2–6 flow-
ered. Flowers thickly tex-
tured, yellow, lip disk with
a chestnut blotch on either
side.
Flowering: April- May
Habitat: Epiphytic on tree
trunks in dense forests,
lithophytic on wet rocks in valleys.
Distribution: China, Bhutan, northern India, Laos, Myanmar, Nepal, northern
Thailand, Vietnam.
Dendrobium chryseum Rolfe, Gard. Chron., III, 3: 233 (1888); Hook. f., F l.
Brit. Ind. 5: 748 (1890); Mishra, Orch. India, 292 (2007).
Dendrobium aurantiacum Rchb.f., Gard. Chron. 1887(2): 98 (1887), nom. illeg. (a
synonym).
Stems cylindric, usually 25–35 cm, slender. Leaves linear or narrowly oblong, 8–
10 × 0.4–1.4 cm, leathery, base sheathing, apex obtuse and emarginate or some-
times subacute and obliquely hooked. Inflorescence lateral on old leafless stem, 1
cm usually 1 or 2 flowered. Flowers spreading, 6.5 cm wide, concolorous yellow,
The MIOS Journal 15(8): 5-24. 2014. Gogoi, K. et al. Orchids in Assam, India: The Genus Dendrob...
Fig. 12. Dendrobium chrysanthum Wall. ex Lindl., 1830.
17
center a darker shade, occasionally with large purple spots on sepals and petals and
a purple spot on lip disk, inner surface of lip sometimes with several red stripes.
Flowering: May- June.
Habitat: Epiphytic on tree trunks in high-mountain broad-leaved forests.
Distribution: NE India, Myanmar, China.
N.B. Dendrobium chryseum has been
more widely known as D. aurantiacum H.
G. Reichenbach.
Dendrobium chrysotoxum Lindl., Ed-
wards's Bot. Reg. 33: t. 19 (1847); Hook.
f., Fl. Brit. Ind. 5: 750 (1890); Chowdhry,
Orch. Fl. Arunachal Prad., 293 (1998);
Pradhan, Indian Orchid-II, 305 (1979);
Mishra, Orch. India, 292 (2)007. [Fig. 13]
Callista chrysotoxa (Lindl.) Kuntze,
Revis. Gen. Pl. 2: 654 (1891).
Dendrobium suavissimum Rchb.f., Gard.
Chron. 1874(1): 406 (1874).
Stem pseudobulbous, erect, fusiform, 6–30 cm. Leaves 2–5, subterminal, oblong,
to 19 × 2–3.5 cm or wider, leathery, base contracted, apex acute and hooked. Inflo-
rescence subterminal, ascending or slightly pendulous, to 20 cm, laxly many flow-
ered. Flowers slightly fragrant, thickly textured, golden yellow, lip deeper golden
yellow with red stripes on each side at base, anther cap pale yellow.
Flowering: April-June
Habitat: Epiphytic on tree trunks in
sunny evergreen broad-leaved forests,
lithophytic on rocks in open forests.
Distribution: China, NE India, Laos,
Myanmar, Thailand, Vietnam.
Dendrobium crepidatum Lindl. &
Paxton, Paxton's Fl. Gard. 1: 63
(1850); Hook. f., Fl. Brit. Ind. 5: 740
(1890); Chowdhry, Orch. Fl. Aruna-
chal Prad., 293 (1998); Pradhan, Indi-
an Orchid-II, 319 (1979); Mishra,
Orch. India, 292 (2007). [Fig. 14]
Dendrobium lawianum Lindl., J.
Proc. Linn. Soc., Bot. 3: 10 (1858).
Epiphytic, stem short, tufted, suberect
to pendulous, terete, striated, 40–45
cm long, many noded, covered with a
papery sheath, slender, pendulous, internodes striate. Leaves 5–9, oblong to nar-
rowly lanceolate, acute. Flowers in pairs from the nodes, white tinged with lilac,
The MIOS Journal 15(8): 5-24. 2014. Gogoi, K. et al. Orchids in Assam, India: The Genus Dendrob...
Fig. 13. Dendrobium chrysotoxum Lindl., 1847.
Fig. 14. Dendrobium crepidatum Lindl. & Paxton, Paxton's Fl. Gard. 1: 63. 1850.
18
waxy; lip simple, white with a large yellow blotch.
Flowering: March – April.
Habitat: Epiphytic on tree trunks in evergreen forests, lithophytic on rocks in open
forests.
Distribution: Hainan, China, Bangladesh, India, Nepal, Sikkim, Myanmar, Thai-
land, Laos and Vietnam.
Dendrobium cumulatum
Lindl., Gard. Chron. 1855:
756 (1855); Hook. f. Fl.
Brit. India, 5: 731 (1890);
Pradhan, Indian Orchid-II,
342 (1979); Chowdhry,
Orch. Fl. Arunachal Prad.,
295 (1998); Mishra, Orch.
India, 292 (2007). [Fig. 15]
Callista cumulata (Lindl.)
Kuntze, Revis. Gen. Pl. 2:
654 (1891).
Dendrobium eoum Ridl., J.
Linn. Soc., Bot. 32: 261
(1896).
Epiphytic, stem erect, 15–60
cm long, slender, pendulous,
internodes striate; leaves 5–
10×1–2cm, oblong-lanceolate,
acute; inflorescence corym-
biform 4–5 cm long; flowers 3.5 cm long, flowers white with purple, pendent.
Flowering: March – May.
Habitat: Epiphyte on tree trunk in forest along a small stream.
Distribution: India, Nepal, Bhutan, Myanmar, Thailand, Cambodia, Vietnam, Bor-
neo.
Dendrobium darjeelingense Pradhan, Indian Orchids: Guide Identif. & Cult. 2:
336 (1979); Mishra, Orch. India, 292 (2007).
Epiphytic, Pseudobulbs conical to fusiform, 1–3 cm high, 5–7 mm in diameter.
Inflorescence 2–3, from nodes, 9–15 mm long, 2–5 flowered. Flower pale-green in
colour.
Flowering: November – January.
Habitat: Epiphyte on tree trunk.
Distribution: India (Assam, Darjeeling).
Dendrobium densiflorum Wallich, Pl. Asiat. Rar. 1: 34 (1830); Hook. f., F l. Brit.
Ind. 5: 748 (1890); Chowdhry, Orch. Fl. Arunachal Prad., 295 (1998); Pradhan,
Indian Orchid-II, 305 (1979); Barua, Orch. Fl. Kamrup dist. 165 (2001); Mishra,
Orch. India, 292 (2007). [Fig. 16]
The MIOS Journal 15(8): 5-24. 2014. Gogoi, K. et al. Orchids in Assam, India: The Genus Dendrob...
Fig. 15. Dendrobium cumulatum Lindl., 1855.
19
Callista densiflora (Lindl.)
Kuntze, Revis. Gen. Pl. 2: 654
(1891).
Dendrobium clavatum Roxb., Fl.
Ind. ed. 1832, 3: 481 (1832).
Stems strongly clavate, swollen,
25–40 cm. Leaves 3 or 4, sub-
terminal, oblong-lanceolate, 8–17
× 2.6–6 cm, leathery, base not
decurrent into clasping sheath,
apex acute. Inflorescence sub-
terminal, pendulous, densely
many flowered. Flowers spread-
ing, 3–4 cm across; sepals and
petals pale yellow, lip golden
yellow, column and anther cap
orange-yellow.
Flowering: April-July
Habitat: Epiphytic on tree trunks
in evergreen broad-leaved forests, lithophytic on rocks in mountain valleys.
Distribution: China, Bhutan, NE India, Myanmar, Nepal, northern Thailand.
Dendrobium devonianum Paxton,
Paxton's Mag. Bot. 7: 169 (1840);
Hook. f., Fl. Brit. Ind. 5: 743 (1890);
Chowdhry, Orch. Fl. Arunachal Prad.,
298 (1998); Pradhan, Indian Orchid-II,
318 (1979); Mishra, Orch. India, 292
(2007). [Fig. 17]
Callista devoniana (Paxton) Kuntze,
Revis. Gen. Pl. 2: 654 (1891).
Dendrobium moulmeinense
C.S.P.Parish ex Hook.f., Fl. Brit. India
5: 746 (1890).
Stems pendulous, cylindric, 50–90 cm,
slender, 3–5 mm in diam., slightly
fleshy. Leaves narrowly ovate-
lanceolate, 8–13 × 1.2–2.5 cm, leathery,
base with clasping sheath, apex long
acuminate. Inflorescences often several, 1- or 2-flowered. Flowers scented, spread-
ing, thinly textured; dorsal sepal white, upper part tinged with purplish red, veins
purple, lip white, front purplish red, with purplish red stripes on both sides below
middle, disk with a yellow spot on either side.
Flowering: March-June
Habitat: Epiphytic on tree trunks in thick mountain forests.
Distribution: China, Bhutan, NE India, Myanmar, northern Thailand, Vietnam.
The MIOS Journal 15(8): 5-24. 2014. Gogoi, K. et al. Orchids in Assam, India: The Genus Dendrob...
Fig. 16. Dendrobium densiflorum Wallich., 1830.
Fig. 17. Dendrobium devonianum Paxton., 1840.
20
Dendrobium eriiflorum Griff., Ic. Pl. Asiat. 3: 316 (1851); Hook. f., F l. Brit. Ind.
5: 715 (1890); Chowdhry, Orch. Fl. Arunachal Prad., 298 (1998); Pradhan, Indian
Orchid-II, 338 (1979); Mishra, Orch. India, 293 (2007). [Fig. 18]
Callista eriiflora (Griff.) Kuntze, Revis. Gen. Pl. 2: 654 (1891).
Dendrobium eriiflorum var.
sikkimense Lucksom, Orchids
Sikkim N. E. Himalaya: 631
(2007), no type.
Epiphyte. Stem7.5–20.5 cm
long, erect, clustered, fleshy
at the base, covered with
sheaths. Leaves many, 4–8 ×
0.5–1 cm, deciduous, linear-
lanceolate, acute. Inflo-
rescence erect to arching, 4–8
cm long, laxly, 6–10 flow-
ered. Flowers 1.5-2 cm
across, greenish white.
Flowering: August-October.
Habitat: Epiphytic on tree
trunks in subtropical forests.
Distribution: India, Nepal,
Bhutan, Myanamar and Ma-
laysia.
Dendrobium falconeri Hook., Bot. Mag. 82: t. 4944 (1856); Hook. f., Fl. Brit. Ind.
5: 742 (1890); Chowdhry, Orch.
Fl. Arunachal Prad., 298 (1998);
Pradhan, Indian Orchid-II, 318
(1979); Mishra, Orch. India, 298
(2007). [Fig. 19]
Callista falconeri (Hook.) Kuntze,
Revis. Gen. Pl. 2: 654 (1891).
Epiphyte. Stem 30–90 cm long,
beaded, pendent, slender, swollen
at nodes, bearing many branchlets,
internodes ribbed. Leaves few, 5–
10×0.15–0.4 cm, linear, many
nerved. Inflorescence fasciculate,
lateral, arising from nodes, 1 or
rarely 2 flowered. Flowers 5–7.5
cm across, spreading, pale yellow.
Flowering: April-May.
Habitat: Epiphytic on tree trunks
forests.
Distribution: India, Bhutan, China and Myanmar.
The MIOS Journal 15(8): 5-24. 2014. Gogoi, K. et al. Orchids in Assam, India: The Genus Dendrob...
Fig. 18. Dendrobium eriiflorum Griff., 1851.
Fig. 19. Dendrobium falconeri Hook., 1856.
21
Dendrobium farmeri Paxton, Paxton's Mag. Bot. 15: 241 (1849); Hook. f., F l.
Brit. Ind. 5: 750 (1890); Chowdhry, Orch. Fl. Arunachal Prad., 298 (1998); Pra-
dhan, Indian Orchid-II, 306 (1979); Mishra, Orch. India, 293 (2007). [Fig. 20]
Callista farmeri (Paxton) Kuntze, Revis. Gen. Pl. 2: 654 (1891).
Epiphyte. Stem 15–45 cm long, clavate, 4–5 angled erect, narrowed towards slen-
der base. Leaves 2–
3, sub-terminal, 8–
20×3.2–5.9 cm,
ovate-lanceolate to
elliptic lanceolate,
acute coriaceous,
many nerved. Inflo-
rescence 10–20 cm
long, axillary, de-
curved, pendent,
many flowered.
Flowers 4–5 cm
across, pale- mauve,
turning into pure
white at maturity.
Flowering: April-
May.
Habitat: Epiphytic
on tree trunks for-
ests.
Distribution: India,
Malaysia, Myan-
mar, Nepal, Thai-
land, Vietnam.
Dendrobium fimbriatum Hook., Exot. F l. 1: t. 71 (1823); Hook Fl. Brit. Ind. 5,
745 (1890); Chowdhry, Orch. Fl. Aunachal Prad., 301 (1998); Pradhan, Ind. Or-
chid-II, 309 (1979); Barua, Orch. Fl. Kamrup Dist., 163 (2001); Mishra, Orch.
India, 293 (2007).
Callista fimbriata (Hook.) Kuntze, Revis. Gen. Pl. 2: 653 (1891).
Epiphytic, Stems rigid, decumbent or pendulous, cylindric or sometimes slightly
fusiform above base, 75–150 cm long, stout. Leaves several, lanceolate, acumin-
ate, gradually tapering to an aute apex ,10–15× 1.5–2.8 cm, leathery. Inflores-
cences racemose, racemes on leafy or leafless stem, lateral, pendulous, subapical,
15–20 cm long, 8–12 flowers each. Flowers 4–5 cm across, sepals and petals gold-
en yellow, lip yellow, with purplish red stripes at base, disk with a deep purple
marking.
Flowering: March – May.
Habitat: Epiphyte in mixed deciduous forest, also in humid evergreen forest.
Distribution: India, Nepal, Bhutan, Burma, China, Thailand, Vietnam.
The MIOS Journal 15(8): 5-24. 2014. Gogoi, K. et al. Orchids in Assam, India: The Genus Dendrob...
Fig. 20a. Dendrobium farmeri Paxton., 1849.
22
Key to the varieties of D. fimbriatum
1a. Lip with a dark maroon blotch, var. oculatum.
1b. Lip without a dark maroon blotch, var. fimbriatum.
1a. var. oculatum Hook. f. Fl. Brit India, 5, 745 (1890). [Fig. 21]
Flowers yellow or bright orange yellow, lip with dark maroon blotch.
1b. var. fimbriatum; in Chowdhary, Orch. Fl. Arunachal Prad., 301 (1998). [Fig.
22] Flowers bright orange yellow, lip without a dark maroon blotch.
Dendrobium formosum Roxb. ex Lindl. in Wall., Pl. Asiat. Rar. 1: 34, t. 39
(1830); Hook. f., Fl. Brit. India 5: 721 (1890); Chowdhry, Orch. Fl. Arunachal
Prad., 301 (1998); Pradhan, Indian Orchid-
II, 328 (1979); Barua , Orch. Fl. Kamrup
dist. 168 (2001); Mishra, Orch. India, 293
(2007). [Fig. 23]
Callista formosa (Roxb. ex Lindl.) Kuntze,
Revis. Gen. Pl. 2: 654 (1891).
Stems terete, thick, ridged, erect (pointed
upwards), woody, sheathed, swollen at the
base tapering towards tip. Leaves oblong,
obliquely subacute, emarginated, sessile,
distichous 2–2.9 × 0.5–0.9 cm. Inflo-
rescence towards the tip 3–4 flowered.
Flowers fragrant, 5–9cm across, white; lip
with large central yellowish-orange blotch.
Flowering: June – July.
Habitat: Epiphyte in tropical forest. Uncommonly found in some isolated patches
in dense forested areas.
Distribution: India, Nepal, Bhutan, Bangladesh, Myanmar, Thailand, Vietnam.
The MIOS Journal 15(8): 5-24. 2014. Gogoi, K. et al. Orchids in Assam, India: The Genus Dendrob...
Fig. 21. D. fimbriatum var. oculatum. Fig. 22. D. fimbriatum var. fimbriatum.
Fig. 23. D. formosum Roxb. ex Lindl., 1830.
23
Dendrobium fugax Rchb.f., Gard. Chron. 1871: 1257 (1871); Hook. f., F l. Brit.
India, 5: 752 (1890).
Flickingeria fugax (Rchb.f.)
Seidenf., Dansk Bot. Ark. 34:
46 (1980). [Fig. 24]
Epiphyte, 70–80 cm long, pen-
dulous; rhizomes creeping;
stems woody, polished; pseu-
dobulbs at irregular distance
on stems, fusiform, 4–6 cm
long. Leaves solitary, terminal,
narrowly oblong, 10–20 × 2–3
cm sessile. Flowers white, 1 or
2, arising at the base of leaf, 3
–3.5 cm across, fugacious.
Flowering: March – October.
Habitat: Epiphyte in humid
evergreen forest, mixed decid-
uous forest.
Distribution: China, Bhutan,
northeastern India, Myanmar,
Thailand and Vietnam.
Dendrobium gibsonii Paxton, Paxton's Mag. Bot. 5: 169 (1838); Hook. f., Fl. Brit.
Ind. 5: 746 (1890); Chowdhry, Orch. Fl. Arunachal Prad., 302 (1998); Pradhan,
Indian Orchid-II, 309 (1979); Mishra, Orch. India, 293 (2007).
Callista gibsonii (Paxton) Kuntze, Revis. Gen. Pl. 2: 654 (1891).
Epiphytic or Epilithic. Pseudobulbs 60–120 cm long. slender, tapering upwards.
Leaves several, 6.5–15.5 × 2.5–5 cm, ovate- lanceolate to lanceolate, shortly acu-
minate. Inflorescence 9–20 cm long, pendulous. Flowers 3–4 cm across, orange-
yelllow.
Flowering: May- August.
Habitat: Epiphyte in humid evergreen forest, mixed deciduous forest.
Distribution: India, Bhutan, Myanmar, Thailand and Nepal.
Dendrobium griffithianum Lindl., Edwards's Bot. Reg. 21: t. 1756 (1835); Hook.
f., Fl. Brit. Ind. 5: 749 (1890); Mishra, Orch. India, 293 (2007).
Callista griffithiana (Lindl.) Kuntze, Revis. Gen. Pl. 2: 654 (1891).
Stems 30.5–45.5 cm long, 4 angled, elongate, calvate-fusiform, thicker towards
the apex, deeply sulcate, to 5 noded, shiney, yellow. Leaves 2 to 3, apical, leath-
ery, oblong-lanceolate, shortly petiolate, acute. Inflorescence 15–25 cm long, sub-
erect to pendant, loosely many flowered. Flowers 4.5–6 cm across, long-lasting,
yellow.
Flowering: April- May
Habitat: Epiphytic, high up on trees.
Distribution: India (Assam), Myanmar, and Thailand.
The MIOS Journal 15(8): 5-24. 2014. Gogoi, K. et al. Orchids in Assam, India: The Genus Dendrob...
Fig. 24. Dendrobium fugax Rchb.f., 1871.
24
Dendrobium heterocarpum Wall. ex Lindl., Gen. Sp. Orchid. Pl.: 78 (1830);
Hook. f., Fl. Brit. Ind. 5: 737
(1890); Chowdhry, Orch. Fl.
Arunachal Prad., 302 (1998);
Mishra, Orch. India, 293 (2007).
[Fig. 25]
Callista heterocarpa (Wall. ex
Lindl.) Kuntze, Revis. Gen. Pl.
2: 654 (1891).
Stems often ascending, 5–27 cm,
thickly fleshy, base contracted,
thickened toward apex. Leaves
oblong-lanceolate, usually 7–10
× 1.2–2 cm, leathery, apex acute
or slightly obtuse. Inflorescence
a raceme arising from apical part
of deciduous old stem, 1–4 flow-
ered. Flowers scented, spread-
ing; sepals and petals silver-
white or creamy yellow, lateral
lobes of lip yellow with red striation, mid-lobe silver or creamy yellow, column
white, purplish red on sides, yellow on inner surface, foot yellow.
Flowering: April- May
Habitat: Epiphytic on trees in sunny open forests.
Distribution: China, Bhutan, India, Indonesia, Laos, Malaysia, Myanmar, Nepal,
Philippines, Sri Lanka, Thailand, Vietnam.
Dendrobium hookerianum Lindl., J . Proc. Linn. Soc., Bot. 3: 8 (1858); Hook. f.,
Fl. Brit. Ind. 5: 745 (1890); Chowdhry, Orch. Fl. Arunachal Prad., 302 (1998);
Pradhan, Indian Orchid-II, 322 (1979); Mishra, Orch. India, 293 (2007).
Callista hookeriana (Lindl.) Kuntze, Revis. Gen. Pl. 2: 654 (1891).
Dendrobium chrysotis Rchb. f., Gard. Chron. 1870: 1311 (1870).
Dendrobium fimbriatum var. bimaculosum Tang & Wang, Acta Phytotax. Sin. 1:
81 (1951).
Stems pendulous, cylindric, 30–80 cm, rigid. Leaves alternate along entire stem,
ovate-lanceolate or oblong, 7–17 × 2–3.5 cm, leathery, acute. Inflorescences 1 to
several, along distal part of current season’s mature leafy stems, 4–10 cm, laxly 2–
7 flowered. Flowers spreading, thinly textured, golden yellow, disk with a purple
blotch on each side.
Flowering: August- September.
Habitat: Lithophytic on rocks in mountain valleys, epiphytic on tree trunks in
mountain forests.
Distribution: China and India.
Paper to be concluded next issue.
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The MIOS Journal 15(8): 5-24. 2014. Gogoi, K. et al. Orchids in Assam, India: The Genus Dendrob...
Fig. 25. Dendrobium heterocarpum Wall ex Lindl., 1830.