Introduction
Isoptera are small, soft-bodied, yellowish, whitish,
tan or black insects that live in colonies in wood. Colonies consist of three
castes: workers, soldiers and swarmers . Workers and soldiers are wingless and
never leave the colony. Swarmers , or the reproductive forms, have dark bodies
and four long, veined wings. The front and hind wings of termites are nearly
identical in size and venation. Termites also have beadlike antennae and thick
waists which distinguish them from ants.
Termites are usually the most dominant organisms in
tropical forest environments. Their populations typically range from 2000
to 4000 individuals per square meter but may occasionally run as high as 10,000
individuals per square meter.
Scientific Classification
of Isoptera
Kingdom: Animalia
Phylum:
Arthropoda
Superclase: Hexapoda
Class: Insecta
Subclass: Pterygota
Infraclass: Neoptera
Order: Isoptera
Distribution
} Extremely common in tropical and subtropical
climates. Generally less abundant in temperate regions.
} Isopteran are hemimetabola(egg, nymph, adult)
Characteristics of
Isoptera(Termites)
Ø Pale, elongate body
Ø 2 pairs of membranous wings of equal length. Wings
are present in reproductive
castes only and shed after mating
Ø Mandibulate(chewing) mouthparts
Ø Antennae about the same length as the head
Physical Features
Immatures (Workers &
Soldiers)
Body pale in color, somewhat
ant-like in appearance but with a
broader junction between thorax and abdomen Compound eyes small or absent.
Ø Head large and cylindrical or small and round.
Ø Antennae beaded.
Ø Mouthparts chewing; sometimes with large mandibles.
Adult
Ø Body may be darkly pigmented Head well-developed,
with chewing mouthparts and beaded antennae.
Ø Compound eyes present.
Ø Two pairs of membranous wings, all similar in shape
and size; wings are shed after mating.
Feeding
Termites feed on a wide
variety of plant material, which may include wood, bark, leaves, grasses,
fungi, humus or the droppings of herbivores. Some species forage on the surface
at night collecting grasses which they take back to be stored in the nest.
Families of order Isoptera
There are 7 families
present worldwide with more than 2300 species.
Important families of isoptera
} In 7 families of order isoptera that is only 4
families are very important which are as
follows.
v Rhinotermitidae (Subterranean termites)
v Kalotermitidae (Drywood and dampwood termites)
v Hodotermitidae (Rottenwood termites)
v Termitidae
Family:
Rhinotermitidae (Subterranean termites)
} These insects build nests in the soil and generally
infest wood that is in contact with the ground.
} This family
includes the most destructive species
Family:
Kalotermitidae (Drywood and dampwood termites)
} These insects nest in the wood itself and do not
require contact with the soil. Pest species include the western drywood
termite (Incisitermes minor) and the forest tree termite (Neotermes
connexus)
Family:
Hodotermitidae (Rottenwood termites)
Generally found inhabiting
moist wood. Contact with the soil is not a requirement. This
family includes the Pacific dampwood termite, Zootermopsis
angusticollis.
Family: Termitidae
} This is the largest family of termites worldwide,
but all of the North American species are relatively minor in importance.
} Adults have three or four heavy veins along the
front edge of the wing, the cerci have five or six segments and the antennae
have 20 or more segments.
Termites are an important
part of the community of decomposers. They are abundant in tropical and
subtropical environments where they help break down and recycle up to one third
of the annual production of dead wood. Termites become economic pests
when their appetite for wood and wood products extends to human homes, building
materials, forests, and other commercial products. In the United States
alone, annual losses due to termite infestations are estimated at more than 800
million dollars.
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