The
term parasitoid wasp refers to a large evolutionary grade of hymenopteran
super-families,
mainly in the Apocrita. The parasitic or
parasitoidal Apocrita are divided into some dozens of families. Many of them
are considered beneficial to humans because they control populations of
agricultural pests. Others are unwelcome because they are hyper
parasitoids, attacking beneficial parasitoids. On the other hand, Fleas
are the insects
forming the order Siphonaptera. They are wingless, with
mouthparts adapted for piercing skin and sucking blood. Fleas are
external parasites,
living by haematophagy
of the blood of
the host.
WASP
PARASITOIDS
Life history
Inside
the host, the egg hatches into larvae.
Larvae feeds inside the host until ready to pupate, which by then is generally
either dead or moribund. Depending on its species, the
parasitoid then may eat its way out of the host or remain in the more or less
empty skin. In either case it then generally spins a cocoon and pupates. Some
wasps rely on the polydnavirus in their lifecycle as viruses provide certain
protection to larva inside the host by weakening the host’s immune system.
Biology
Parasitoidal
wasps range from some of the smallest species of insects, to wasps about an
inch long. Some are parasitoids that complete their metamorphosis in a single
small egg of an insect, and is usually less than 1mm long. Most females have a
‘spine-like’ ovipositor at the tip of the abdomen.
Conservation and ecological role
Wasps
are economically and environmentally important because their larvae feed on and destroy many insects
that are injurious to humans and plants, especially to food crops. The
ichneumon wasps play a role in the control of agricultural pests. They act as
biological control agents. They are important insects as they are consumers
(third and fourth trophic level) in the food web and play a vital role, in a
multi-trophic interaction context, in natural communities.
FLEAS
Life
history
The
flea egg hatches vary from two days to a few weeks. The larva emerges from
the egg using a chitin tooth. After about 5 to 18 days, larva spins a silken
cocoon and pupates. This brings us back to the adult flea. Adult fleas must
feed on blood before they can become capable of reproduction.
Biology
Fleas
have a laterally compressed body, a tough, smooth cuticle with many
backward-projecting bristles, and relatively long legs with stylets mouths used
for blood sucking.
Conservation and ecological role
They
serve as food for ants and beetles. Besides the problems posed by the creature
itself, fleas can also act as a vector for disease. Fleas transmit not only a
variety of viral, bacterial and rickettsial diseases to humans and other
animals, but also protozoans and helminthes.
Share
with us your experiences, comments and recommendations. Send emails to wildlifemgtsociety@gmail.com
No comments:
Post a Comment