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Current Category » Fundamentals to Entomology

Insect Order: Orthoptera

Order – Orthoptera (Orthos – Straight & pteron =wing)
e.g. Grass hoppers, Locusts, Crickets

Economic Importance: Majority of insects are phytophagous, almost terrestrial, and capable of jumping actively. Short horned grasshoppers, locust, surface grasshoppers are crop pests.

Characters:

1. Medium to large sized insects with hypognathous head position, Mandibulate types of mouthparts.
2. Antennae elongated filiform or short (Thread like).
3. Prothorax large and distinct (Saddle like).
4. Hind legs usually enlarged and modified for jumping, tarsi 3 or 4 segmented.
5. Forewings forming more or less thickened tegmina with submarginal costal vein.
6. Wing pads of nymph undergo reversal during development.
7. Female generally with well developed ovipositor, not concealed by 7th or 8th abdominal sterna.
8. Male externally genitalia symmetrical, concealed at rest by enlarged 9th abdominal sternum.
9. Cerci usually short invariably unsegmented.
10. Specialized auditory and stridulatory organs, frequently developed.
11. Metamorphosis is slight.

The order has been classified into following two sub-orders:

Sub-order: Ensifera:

1. Antennae as long as or longer than the body with many segment.
2. Tympanal organ when present, on fore tibiae (A pair of tympanal organ at the base of each tibia).
3. Stridulatory organ when present usually (allary tegminal).
4. Ovipositor more or less elongated.

Sub-order: Caelifera:

1. Antennae shorter than body with less than 30 segments.
2. Tympanal organ when present at the base of abdomen (on each side of first abdominal tergum).
3. Stridulatory organ varied or absent but typically femoro-allary.
4. Ovipositor short and robust.

Important Families:

1. Tettigonidae: Long horned grasshoppers, Bush crickets etc.
2. Acrididae: Short horned grasshopper, Locust, surface grasshoppers.
3. Grylidae: House and field crickets.
4. Gryllotalpidae: Mole crickets.

Current Category » Fundamentals to Entomology