SCIENCE REPORTER, JUNE 201253

DIPANJAN GHOSH &SREEPARNA GHOSH

EVER since their discovery 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

Ghatparni (locallyknown as Tiew-rakot)is the only pitcherplant of India thatoccurs across a verysmall area inMeghalaya. Presentlyabout twentypopulations of thisplant survive in thewild.

India’s OnlyPitcher PlantIn Peril

The Mocassin plant (Cephalotus follicularis)

Nepenthes hamata

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SCIENCE REPORTER, JUNE 201253

SCIENCE REPORTER, JUNE 2012 54

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 l ike 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

distribution and is almost rare in the wild.

In fact, within a quarter of a century after

independence, the major i ty of N.

khasiana habitats in India had been

destroyed, and the remaining populations

had declined severely as a result of rapid

urbanization and indiscr iminate

specimen col lection for t rading

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

occur in the Jarain, Jowai and Umtra area

of the Jaintia Hil ls, the Baghmara,

Balpakram and Maheskhola area of the

Garo Hil ls, 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’.

The Cobra lily(Darlingtoniacalifornica)

The Sun pitcher(Heliamphorachimantensis)

The North American pitcher plant (Sarracenia rubra)

Nepenthes khasiana or Tiew-rakot (as locally known) in its naturalhabitat at Jowai, Meghalaya (Photo credit: Shreya Middya)

The potential for long-term survival of this species in thewild is uncertain, and will surely depend on thecontinuing efforts of local communities

There are 14 genera ofinsectivorous plants comprisingabout 1000 species, in the plantkingdom.

Ghatparni plantsmainly catch smallinsects, like ants,beetles, bugs, flies,midges, termites, etcand protozoans.Sometimes smallcrabs and snails aretrapped.

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SCIENCE REPORTER, JUNE 201255

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

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

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 l id. 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 very

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

Nutrient deficiency in theinhabiting soil or water bodies hasforced these plants to face suchhardship. Insectivorous plantshave, thus, developed a uniqueway to get the nutrients they needfrom sources other than soil. Theycatch prey in specially adaptedtraps.

Illegal trade inNepenthes plantcontinues unabated.Isolated incidents ofdamaging this rarewonder by students(during theirexcursions) alsohappen frequently.Spontaneousparticipation of localpeople in conservationprogrammes is alsolacking.

Feature Article

Photo by Nachiketa Pramanick and Shreya Meddya

SCIENCE REPORTER, JUNE 2012 56

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 (l ike ants, beetles, bugs, fl ies,

midges, termites, etc) and protozoans.

Sometimes small crabs and snails are

trapped. Unexpectedly some inanimate

agents l ike 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

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 dest ruct ion, decimation of

species and f ragmentat ion of large

contiguous populations into isolated

smal l and scattered ones – have

rendered N. khasiana increasingly

vulnerable in i ts native land. Human

population growth coupled with certain

anthropogenic act iv i t ies such as

deforestation, coal mining, l imestone

extract ion, road and br idge

construction, increasing production of

wastes and pollutants and expanding

agriculture are largely responsible for the

destruct ion 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

time to time by various organizations like

the Centre of Advanced Study in Botany,

North Eastern Hil l University; National

Orchidorium, Shil long; Experimental

Garden of Botanical Survey of India,

Yercaud and by the Ministry of Forests and

Environment, Government of India.

Techniques l ike 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 cont inues unabated. Isolated

incidents of damaging this rare wonder

by students (during their excursions) also

happen f requent ly. Spontaneous

part ic ipat ion of local people in

conservat ion 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 sti l l

remain.

Mr Dipanjan Ghosh is a postgraduate teacher inBiology in a Govt. Sponsored Higher SecondarySchool situated in Burdwan, West Bengal. Address:Chotonilpur Pirtala, P.O. Sripally, Dist. Bardhaman-713103, West Bengal; Email:dpanjanghosh@gmail.com

Ms Sreeparna Ghosh is associated with an NGOthat is engaged in environmental problems andchildren’s awareness through education; Email:zeenaghosh@gmail.com

Photo by Nachiketa Pramanick and Shreya Meddya

These carnivorous plantsderive some or most of theirnutrients (but not energy)from trapping andconsuming animals orprotozoans, typicallyinsects and otherarthropods. Insectivorousplants are the only plantgroup in the entire plantkingdom that live byhunting tiny animals.

Feature Article