The insect integument, or exoskeleton, consists of three main layers: 1. The cuticle, which is the outermost layer and provides protection. It has two regions - the epicuticle and procuticle. 2. The epidermis, which secretes the cuticle and aids in molting. 3. The basement membrane between the epidermis and organs. The cuticle protects the insect, prevents water loss, and helps insects maintain their shape. It is rigid yet lightweight and allows for various modes of life.

1. Insect Integument
Snehal Arun Mane
Dept. of Entomology

2. Integument or Body Wall
• Insect body wall is
called as
Integument or
Exoskeleton.
• It is the external
covering of the
body which is
ectodermal in
origin.

3. • It is rigid, flexible, lighter,
stronger and variously modified
in different body parts to suit
different modes of life.
• Serves as a protective covering
over the body, also know
integument

4. • The insect integument consisting of
1.The cuticle
2.The epidermis or hypodermis
3.The basement membrane

5. Insect Integument (Exoskeleton)
Outer epicuticle
Inner epicuticle
Epicuticle
Exocuticle
Endocuticle
Schmidt’s layer
Epidermis
Basement membrane
Pore canals
Procuticle

7. • It is complex non cellular layer .
• It is outermost thick layer of
integument
• Secreted by epidermis .
• When newly formed it is flexible
and elastic .
• When undergoes sclerotization it
becomes hardened and darkened .
1.The cuticle

8. A.The Epicuticle ( Upper )
B. The Procuticle ( Inner )
It is divided in to two regions

9. • It is very thin outer most layer
• Thickness : 0.03 – 4.00
micron.
• Chitin is absent in epicuticle
A.The Epicuticle

10. • Cement layer
• Wax layer
• Polyphenol layer
• Cuticulin layer
It consists of following 4 layers

11. Insect Integument (Exoskeleton)
Why are insects crunchy?
Outer epicuticle
Inner epicuticle
Epicuticle
cement
wax
oriented wax
cuticulin
Inner epicuticle
Exocuticle (procuticle)
pore canal

13. • Secreted by dermal gland
• Composed of lipoprotein
• It protects the body from external
damage.
1. Cement layer

14. • Prominent layer
• Thickness - 0.25 micron
• Consisting long chain hydrocarbons
fatty acids and alcohols
• It serves as water proof layer
• Preventing water loss from the body
2.Wax layer

15. • Consisting phenols which are
mainly used in the formation of
proteins.
• Resistant to acids and organic
solvents.
3.Polyphenol layer

16. • It is amber colure thin layer
• Act as growth barrier.
4.Cuticulin layer

17. B.Procuticle
• Exocuticle
• Darkly pigmented
• Hard and
sclerotized
• Consisting mainly
chitin and hard
protein called
Sclerotin.
• Endocuticle
• Light colored
• Soft and
unsclerotized
• Consisting more
chitin
• Lack of Sclerotin

18. • It is single layer of cells lying
below the cuticle.
• Secretes greater part of cuticle
and moulting fluid
2.Epidermis

19. • Epidermis resting on basement
membrane with the following
function.
 Cuticle secretion
 Digestion and absorption of old
cuticle
 Wound repairing
 Gives surface look
3.Basement membrane

20. • Protection to the organs
• Gives shape to insect
• Provides surface for attachment of muscles
• Conserve moisture and prevent desiccation
• Prevent entry of pathogens and insecticides
• It forms sense organ
• Contains pigment to make insect attractive
Functions of body wall

21. Oklahoma State University Oklahoma Master Gardeners

22. Some days you’re the bug,
some days you’re the windshield.
- Mark Knopfler