Insect wing by Dr chetna khandakar dept of entomology.sgcars Jdb

1. Presented by
Dr. CHETNA KHANDEKAR
Dept. of Entomology
INSECT WINGS AND ITS
MODIFICATION

2. INSECT WINGS
 Wings arises from meso (forewings) and meta (hind wings)
thoracic segments
 Normally two pairs of wings are present in insects and they are
borneon pterothoracic segments viz., mesothorax and metathorax.
 Almost all Insects possess 2 pairs of wings.
 There is only one pair of wings in the true flies.
 Certain primitive insects like silver fish and spring tail have no
wings (apterous).
 Ecto parasites like head louse, poultry louse and flea are
secondarily wingless.
 Wings are deciduous (shed their wings) in ants and termites.

3.  Based on the degree of development of
wings the insects may be classified into
1. Macropterous- having long or large
wings
2. Brachypterous- having short or reduced
wings
3. Apterous- having no wings or wingless

4. Modification of wings

5. 1. TEGMINA
 Tegmina (singular tegmen) are the leathery forewings
of insects in the orders Orthoptera, Blattaria, and
Mantodea.
 The tegmina help to protect the delicate hind wings.
 Examples: Grasshoppers, crickets and katydids (order
Orthoptera), Cockroaches (order Blattaria), Mantids
(order Mantodea).

7. 2. ELYTRA
 Elytra (singular elytron) are the hardened, heavily
sclerotized forewings of beetles
 They are modified to protect the membranous hind
wings when at rest.
 Examples: All beetles (order Coleoptera).

9. 3. HEMIELYTRA
 A variation of the elytra is the hemelytra.
 The forewings of Hemipterans are said to be
hemelytrous because they are hardened throughout the
proximal two-thirds, while the distal portion is
membranous.
 Hemielytra function primarily as flight wings.
 Examples: Bugs (order Hemiptera).

11. 4. HALTERES
 Halteres are an extreme modification in hindwings among
the order Diptera (true flies)
 In true flies the hind wings are modified into small
knobbed vibrating organs called haltare.
 Each haltere is a slender rod clubbed at the free end
(capitellum) and enlarged at the base (scabellum).
 They act as balancing organs and provide the needed
stability during flight.
 Examples- true flies, mosquito, male scale insect.

13. 5. Pseudohaltere
 They are short and
modified into
pseudohalteres which
are dumbbell shaped.
 Eg: Front wings of
Strepsiptera

14. 6. MEMBRANOUS WINGS
 Membranous wings are thin and more or less
transparent, but some are darkened.
 Transparent wings are called membranous wings.
 They are thin and supported by a system of tubular
veins.
 In many insects either forewings or hind wings or both
fore wings and hind wings are membranous.
 They are useful in flight.
 Examples: Dragonfiles and damselflies (order
Odonata), lacewings (order Neuroptera), flies (order
 Diptera), bees and wasps (order Hymenoptera),
termites (order Isoptera).

16. 7. SCALES
 Wings of butterfly and moths are covered with small
coloured scales.
 Scales are unicellular flattened outgrowth of body wall.
 Scales are inclined to the wing surface and overlap each
other to form a complete covering.
 Scales are responsible for colour.
 They are important in smoothing the air flow over wings
and body.
 Examples: Butterflies, moths and skippers (order
Lepidoptera), caddisflies (order Trichoptera)

18. 8. Fringed wings
 Wings are usually
reduced in size.
 Wing margins are
fringed with long
setae.
 These insects
literally swim
through the air.
 e.g. Thrips

19. 9. Fissured wings
 Forewings are
longitudinally divided
twice forming a fork like
structure whereas
hindwings are divided
twice in to three arms.
 All the forks possess small
marginal hairs . They are
useful for flight.
 e.g. Both the wings of
plume moth