Egg types



















TYPES OF INSECT EGGS

            Egg is the first stage of development in all insects. The outer cover or the egg shell is called chorion. The chorion is lined within by vitelline membrane, which encloses the cytoplasm, yolk and nucleus. There is also a minute opening through which the sperm enters the egg for fertilization.

Types of insect eggs
            Insect eggs are much more variable in shape, structure, colour, possession of appendages and the way of laying as described below.


Egg type
Description
Example
Scaly
Flat and scale like
Coding moth
Spherical
Globular, mostly sculptured
Swallowtail butterfly
Oval
Elliptical
Japanese beetle
Conical
Cone like
Cabbage worm
Elongate
Linear, rod shaped
Leafhopper
Barrel
Cylindrical, erect
Plant bugs
Egg float
Single egg with air filled packets, help to be buoyant
Anopheles mosquito
Nit
Cemented to hairs
Head louse
Stalked (pedicellate)
Held erect on slender thread
Aphid lions
Filamentous
Filaments radiating from rim
Water scorpion
Ootheca
Double layered chitinous capsule with 16 eggs arranged in 2 rows
Cockroach
Egg case (ootheca)
Foamy secretion (spumaline), enclosing the eggs, hardens later
Manitids
Egg pod
Mass of eggs held together in frothy secretion, hardens later
Grasshoppers
Egg mass
Eggs covered by body hairs or wing scales
Moths
Egg raft
Laterally attached, mass of eggs floating on water
Culex mosquitoes

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