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Feature Article
DIPANJAN GHOSH &
SREEPARNA GHOSH
Nepenthes hamata
Ghatparni (locally
known as Tiew-rakot)
is the only pitcher
plant of India that
occurs across a very
small area in
Meghalaya. Presently
about twenty
populations of this
plant survive in the
wild.
India’s Only
Pitcher Plant
In Peril
E
VER since their discover y by the
legendary naturalist Charles Darwin
in 1875, insectivorous plants continue
to fascinate due to their devouring nature.
These carnivorous plants derive some or
most of their nutrients (but not energy) from
trapping and consuming animals or
protozoans, typically insects and other
arthropods. Insectivorous plants are the
only plant group in the entire plant kingdom
that live by hunting tiny animals.
Insectivorous plants are adapted to
grow in places where the soil is thin or poor
in nutrients, especially nitrogen, such as
acidic bogs and rock outcroppings.
Nutrient deficiency in the inhabiting soil or
water bodies has forced these plants to
face such hardship. Insectivorous plants
have, thus, developed a unique way to
get the nutrients they need from sources
other than soil. They catch prey in specially
adapted traps. The endogenous enzymes
then digest the proteins and nucleic acids
in the prey, releasing amino acids and
phosphate ions, which the plant
absorbs.
Pitcher plants have a prey-trapping
mechanism that is basically a deep cavity
or pitcher filled with liquid known as pitfall
trap. It has been widely assumed that the
various sorts of pitfall traps have evolved
from rolled leaves. However, pitcher plants
The Mocassin plant (Cephalotus follicularis)
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SCIENCE REPORTER, JUNE 2012
Feature Article
The Sun pitcher
(Heliamphora
chimantensis)
The North American pitcher plant (Sarracenia rubra)
The Cobra lily
(Darlingtonia
californica)
There are 14 genera of
insectivorous plants comprising
about 1000 species, in the plant
kingdom.
are broadly classified into two categories.
The old world pitcher plants are often
climbers, whose pitchers arise from the
terminal portion of the leaves. The new
world pitcher plants are ground-dwelling
herbs, whose pitchers arise from a
horizontal rhizome.
There are 14 genera of insectivorous
plants comprising about 1000 species.
Among them Cephalotus, Darlingtonia,
Heliamphora, Nepenthes and Sarracenia
are the pitcher bearing carnivorous plant
genera. Nepenthes belongs to the
monotypic family Nepenthaceae. It has
about 90 species (including natural hybrids
and cultivars) that are found throughout
the tropical old world countries.
Distribution
The pitcher plant genus Nepenthes is
native to places like North Australia,
Madagascar, India, Sri Lanka, Borneo, New
Guinea, Thailand and Vietnam, as well as
many islands and landmasses around the
Pacific Ocean.
India is home to a single pitcher plant
species, known as Nepenthes khasiana.
This particular species has a very localised
SCIENCE REPORTER, JUNE 2012
Nepenthes khasiana or Tiew-rakot (as locally known) in its natural
habitat at Jowai, Meghalaya (Photo credit: Shreya Middya)
Ghatparni plants
mainly catch small
insects, like ants,
beetles, bugs, flies,
midges, termites, etc
and protozoans.
Sometimes small
crabs and snails are
trapped.
The potential for long-term survival of this species in the
wild is uncertain, and will surely depend on the
continuing efforts of local communities
distribution and is almost rare in the wild.
In fact, within a quarter of a century after
independence, the majority of N.
khasiana habitats in India had been
destroyed, and the remaining populations
had declined severely as a result of rapid
urbanization
and
indiscriminate
specimen collection for trading
purposes.
During the 1970s, in an effort to
protect the remaining stands of this
species in the wild, the Government of
India banned the export of N. khasiana
plants and listed the species as critically
endangered on Appendix I of the
Convention on International Trade in
Endangered Species (CITES). Apart from
N. khasiana, there are a few other (all
found outside India) most threatened
endangered species, such as N.
aristolochiodes, N. clipeata, N. rajah and
N. rigidifolia.
Today
isolated
precarious
populations of N. khasiana are known to
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occur in the Jarain, Jowai and Umtra area
of the Jaintia Hills, the Baghmara,
Balpakram and Maheskhola area of the
Garo
Hills,
and
Lawbah
and
Mawlynnong region of the East Khasi
Hills of Meghalaya within 100-1500 m
altitude, where this species grows
endemically.
‘Monkey Cup’ is the regular
cognomen of all the tropical pitcher plant
species associated with the genus
Nepenthes. This popular name refers to
the fact that monkeys have been
observed drinking rainwater from these
plants. In Hindi, it is known as
‘Ghatparni’.
The aboriginal people of Meghalaya
have a long association with this plant. The
Khasi people call it ‘Tiew-rakot’ meaning
‘demon-flower ’ or ‘devouring plant ’.
Jaintias call it ‘ Kset phare’ which means
‘lidded fly net’ whereas Garo people call
it ‘Memang koksi’ meaning the ‘basket of
the devil’.
Feature Article
Illegal trade in
Nepenthes plant
continues unabated.
Isolated incidents of
damaging this rare
wonder by students
(during their
excursions) also
happen frequently.
Spontaneous
participation of local
people in conservation
programmes is also
lacking.
The Plant
Ghatparni grows mostly in moist, acidic
and nutrient-deficient soils, sometimes in
sandy ground and even up cliff faces.
However, the soil needs to be light and
airy. The plant likes to grow as a climbing
or scrambling vine. The long foliage leaves
radiate out in a rosette fashion from a
central climbing stem. N. khasiana has two
types of pitchers – the lower and the upper.
The lower pitchers are up to 12 cm tall
and 4.5 cm wide while the upper pitchers
are up to 21 cm tall and 5 cm wide. The
entire pitcher (both lower and upper) is
tinged with exciting colours. The outer side
of the pitcher is yellowish green or
occasionally orange to pink, sometimes
mottled with faint red or orange blotches.
The inner side of the pitcher is yellow,
orange or pink and the peristome may be
yellow, green, orange, pink or red. The lid
often has a red underside. Some plants
produce pitchers with a faint orange or
reddish band just below the peristome,
making the pitchers more attractive.
N. khasiana flowers between June to
October. The fruit is capsular and 20-25
mm long. A mature fruit contains five
Photo by Nachiketa Pramanick and Shreya Meddya
Nutrient deficiency in the
inhabiting soil or water bodies has
forced these plants to face such
hardship. Insectivorous plants
have, thus, developed a unique
way to get the nutrients they need
from sources other than soil. They
catch prey in specially adapted
traps.
hundred or more seeds. Seeds are very
light and have long wings to be carried by
the wind.
N. khasiana has a few distinctive
characteristics that distinguish it from other
morphologically similar species. It is closely
related to N. distillatoria, and distinguishing
between these plants may not be easy.
The two species differ most obviously in
the form of their inflorescences. N.
distillatoria is with widely spaced tri- to
penta-flowered partial peduncles which
is absent in N. khasiana. The lid of N.
distillatoria is very glandular beneath and
its leaves are slightly decurrent, whereas in
N. khasiana the glands are more diffuse
beneath the lid and the leaves are often
strongly decurrent. The shape of the lids
and colouration of the pitchers also differs
to some extent. Moreover, the lower
pitchers of N. distillatoria are more swollen
in the basal portion than those of N.
khasiana that are comparatively
cylindrical.
Nepenthes khasiana may also be
confused with two other morphologically
similar species such as N. tomoriana and
N. vieillardii. But both the species lack truly
petiolate leaves and their pitchers show
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some superficial variations with that of N.
khasiana. Again, certain populations of N.
mirabilis produce pitchers that resemble
those of N. khasiana, although their finely
fimbriate leaf margin is unknown to N.
khasiana.
Useful Snare
Ghatparni has pitfall traps. Pitfalls are
passive traps. In contrast with other
carnivorous plants, the pitcher plants (as
well as the traps) do not move with their
prey. Insects are attracted by the brightly
coloured pitcher covered with colourful
lid projecting over the mouth or by the
odour of the nectar. Nectar is secreted
from the glands at the entrance of the
pitcher as well as at the lower surface of
the lid. Each pitcher-trap contains a
copious amount of liquid (a mixture of
deposited rainwater and dew drops as
well as enzymatic and acidic secretion).
The inner surface of the pitcher is ver y
slippery.
Once inside, the insect finds it cannot
get a grip on the walls of the pitcher
because a flaky wax on the interior surface
peels off as it struggles to climb. Eventually,
the insect falls into the liquid and struggles
SCIENCE REPORTER, JUNE 2012
Feature Article
These carnivorous plants
derive some or most of their
nutrients (but not energy)
from trapping and
consuming animals or
protozoans, typically
insects and other
arthropods. Insectivorous
plants are the only plant
group in the entire plant
kingdom that live by
hunting tiny animals.
Photo by Nachiketa Pramanick and Shreya Meddya
to escape. The motion caused by the
struggle stimulates digestive glands to
release a proteolytic enzyme and
digestive acid. These two secretor y
materials help in digestion of the prey. Then
numerous absorbing glands of the internal
pitcher wall soak up the extracts of the
digested remains. Besides, in any mature
pitcher, a heap of undigested
exoskeletons are also noticed.
Ghatparni plants mainly catch small
insects (like ants, beetles, bugs, flies,
midges, termites, etc) and protozoans.
Sometimes small crabs and snails are
trapped. Unexpectedly some inanimate
agents like bird droppings or a good
amount of dead plant parts falling from
the forest canopy are also held within the
pitchers and digested. However, the
Malaysian pitcher (Nepenthes rajah), the
largest pitcher bearing plant, is able to trap
comparatively larger preys such as small
reptiles and mammals like mice.
Medicinal Benefits
Nepenthes khasiana has some medicinal
values. Tribals of Khasi, Garo and Jaintia
Hills are acquainted with the medicinal
properties of pitcher plants. Its juice
extracted from the leaves is said to be
helpful for diabetic patients as well as for
those who suffer from difficulties in passing
urine. Khasi and Garo people use the fluid
of the unopened pitcher as an eye-drop
for cataract and night blindness. The
Jaintias use N. khasiana for treating the
inflamed skin, stomach trouble and
gynaecological problems.
The Garos crush the dried plant until it
is reduced to powder. Then this powder is
SCIENCE REPORTER, JUNE 2012
applied as an antidote on leprosy patients.
Apart from certain ethno-medicinal uses,
hypoglycemic and hypolipidemic effect
of N. khasiana has been clinically tested in
rats. Recently researchers at Tel-Aviv
University of Israel have found that the liquid
inside the pitcher contains a compound
that fights off fungal infections by breaking
down the fungi’s chitinous cell wall.
Conservation Crisis
Ghatparni is among the most critically
endangered of all Nepenthes species.
Presently a few populations of this plant
survive in the wild. Three main reasons –
habitat destruction, decimation of
species and fragmentation of large
contiguous populations into isolated
small and scattered ones – have
rendered N. khasiana increasingly
vulnerable in its native land. Human
population growth coupled with certain
anthropogenic activities such as
deforestation, coal mining, limestone
extraction,
road
and
bridge
construction, increasing production of
wastes and pollutants and expanding
agriculture are largely responsible for the
destruction of habitats leading to
decline in the species viability.
However, the main threat to the
pitcher plant ’s existence in accessible
habitats is posed by human collectors. Its
strange shape and carnivorous habit have
made it a curiosity for the common
people, tourists, college and university
students participating in botanical
excursions, and so on.
Various in situ and ex situ conservation
measures have been implemented from
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time to time by various organizations like
the Centre of Advanced Study in Botany,
North Eastern Hill University; National
Orchidorium, Shillong; Experimental
Garden of Botanical Survey of India,
Yercaud and by the Ministry of Forests and
Environment, Government of India.
Techniques
like
tissue
culture,
micropropagation and germplasm
preservation have also been administered
to N. khasiana. As a result, some
populations of N. khasiana are now
permanently protected, although the
result is not fully satisfactory in all the cases.
However, illegal trade in Nepenthes
plant continues unabated. Isolated
incidents of damaging this rare wonder
by students (during their excursions) also
happen
frequently.
Spontaneous
participation of local people in
conservation programmes is also
lacking.
The potential for long-term survival
of this species in the wild is uncertain,
and will surely depend on the continuing
efforts of local communities to preserve
those habitats of Nepenthes that still
remain.
Mr Dipanjan Ghosh is a postgraduate teacher in
Biology in a Govt. Sponsored Higher Secondary
School situated in Burdwan, West Bengal. Address:
Chotonilpur Pirtala, P.O. Sripally, Dist. Bardhaman713103,
West
Bengal;
Email:
[email protected]
Ms Sreeparna Ghosh is associated with an NGO
that is engaged in environmental problems and
children’s awareness through education; Email:
[email protected]