Lesson 4: Insect Parasites

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Lesson 4 Insect Parasites

• The most valuable insect parasites are in the
  following groups
• Tachinid Flies
• Ichneumonid Wasps
• Braconid Wasps
• Chalcid Wasps

These parasites live in or on one host insect
pest which is killed after the parasite completes
its development.
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Lesson 4 Insect Parasites
Tachinid Flies Many species resemble an
overgrown house fly. The fly is usually
grayish, brownish, or black mottled with bristles
(Fig.).
Tachinid Fly
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Lesson 4 Insect Parasites
Tachinid Flies The adult flies rest on foliage
or on flowers upon which they feed. Adults lay
eggs glued to the host or laid on foliage where
the host insect pest may ingest them. Hatched
larvae are also deposited on or in the victim
insect pests. Larvae feed on the contents of host
insect pests.
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Lesson 4 Insect Parasites
Ichneumonid wasps These wasps include a large
number of species and are very widely
distributed. Much variation is found in size,
form, and markings of the adults. Most are
somewhat wasp-like in appearance and many of the
females have very long ovipositors, often longer
than the body (Fig.).
Ichneumonid wasp
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Lesson 4 Insect Parasites
Ichneumonid wasps Most of these wasps are
internal parasites of the immature stages of the
insect pest host. The parasite may complete its
development in the host insect pest. There are
few groups of insects that are not parasitized by
some of these wasps.
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Lesson 4 Insect Parasites
Braconid wasps These wasps are another large
group of parasitic insects. The adults are
relatively small (rarely over 15 mm long) and a
great many are stout-bodied (Fig.).
Braconid wasp
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Lesson 4 Insect Parasites
Braconid wasps These wasps parasitize a wide
range of insects but chiefly aphids and the
larvae of moths, beetles, and flies. The habits
of the braconids are similar to the ichneumonids
except that many of them pupate in silken cocoons
on the outside of the body of the insect host.
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Lesson 4 Insect Parasites
Chalcid wasps These wasps are usually quite
small (2 mm) and in general are metallic blue or
green (Fig.). Many species live inside minute
insects or the eggs of scale insects, aphids,
caterpillars, and flies.
Chalcid wasp
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Module 6 Predators and Parasites
Virtual Academy for the Semi Arid Tropics
Modules
Lessons
End

With this, the Lesson 4 on Insect Parasites,
and also this Module on Predators and Parasites
concludes. With this, the course on Insect
Pests of Sorghum also concludes. To review the
course Click Modules button and select the
Module To end the course Click on End
button given above.
Course on Insect Pests of Sorghum