Diptera is an order of insects comprising flies, mosquitoes, and gnats. They are characterized by having one pair of wings, with the hind wings modified into club-like halteres. The order is divided into three suborders - Nematocera, Brachocera, and Cyclorrhapha - based on antennae morphology. Nematocera have many segmented antennae, Brachocera have three segmented antennae shorter than the head and thorax, and Cyclorrhapha have three segmented antennae with an arista. Each suborder contains multiple families of flies exhibiting distinct physical traits and including important disease vectors like mosquitoes.

1. Diptera
Di=Two Ptera=wings
Examples:Flies,Mosquitoes etc.
Characteristics:
 One pair of wing, Hind wing is Haltare
 Antennae and Mouth Parts are varying in types
 A large and moveable head.
 Compound eyes that are often very large.
Sub-Orders It has 3 Sub-Orders
A) Nematocera:
Characteristics:
 Antennae Many Segmented
 Antennae Longer than Head and Thorax
 In wing,Cubitus is Open
It has 6 Families
1)Tipulidae: (e.g Cran Fly)
 Antennae is long and 6 Segmented
 Legs are very Long.
 The wings are monochromatic, longitudinally striped or marbled.
e.g. Tipula bicornis

2. 2)Psychodidae:(e.g Sand Fly)
 Very Small size insect looks like a moth
 Legs and bodyare covered with hairs
 Radius vein is 4 Branches and No cross vein
e.g. Clogmiaalbipunctata.
3)Culicidae:(e.g Mosquitoes Culex & Anopheles)
a)Antennae is Plumose
Male Mosquito
Dense hairs
b)Antennae is Pilose
Female Mosquito
Thin hairs
 Mosquitoes have a slender segmented body,
 one pair of wings, one pair of halteres,
 three pairs of long hair-like legs, and
 elongated mouthparts.
e.g. Culex pipiens,
4) Cecidomyiidae:(e.g Midges)
• Very minute and delicate insect
• Antennae is Moniliform and hairs on body
• Wings have less no of Longitudinal Veins

3. • Tibia has Spur on it.
 reduced wings,
 . The mouthparts are reduced.
e.g. Contarinia nasturtii
5) Mycetophilidae: (e.g Fungus gnates)
a. Antennae is fairly Long & without hairs
b. Tibia has spur on it.
c. well-developed coxae, and often spinose legs,
e.g. Exechia spinuligera
6) Simuliidae: (e.g Black fly or Biting fly)
 Body is stout(hard Exo-skeleton)
 Antennae is very short & 11 Segmented
 Wings are broad
 Legs are very short
e.g. Simuliumtrifasciatum
B) Brachocera:
 Antennae 3 segmented
 Antennae Shorter than Head and Thorax.
 The maxillary palp (an elongated appendage near the mouth) has two
segments or fewer.
It has 3 Families

4. 1)Tabanidae: (e.g Common House flies)
 3 rd Antennal segment is annulated
 Squama(Structure at the baseof haltare and maintining for balance) is present
 Adult tabanids are large flies with prominent compound eyes.
 The membranous forewings are clear.
e.g. Tabanus sulcifrons
2)Asilidae: (e.g Robber flies)
 Radius(R1) Vein is very Long
 Media(M1) is very short
 Media terminates before the apex of wing.
 The antennae are of the aristate type.
 The mouthparts are short and modified for piercing-sucking.
e.g. Efferia aestuans
3) Bombyliidae: (e.g Bee flies)
 Body have pubescent(densely) hairs on it
 Proboscis is very long
 Legs are long and Rudemantry
e.g. Bombylius major
C) Cyclorrhapha:
 Antennae 3 Segmented
 Arista on it due to Aristate Antennae
It has 7 Families
1) Syrphidae: (e.g Syrphid fly/Hover fly/Flower fly)
 Moderate to large size insect

5.  Body with light yellow colour margins
 Abdomen black colour.
e.g. Syritta pipiens
2) Tephritidae: (e.g Fruit fly)
 Few of its species,wings are bended
 Sub-Costa ends abruptly.
 The head is hemispherical and usually short.
 Ocelli and cellar bristles are present.
e.g Tephrella decipiens
3) Drosophilidae: (e.g Drosophila)
 Post-Occular bristle convergent
 Body is Stout/Swollen.
 presence of an incomplete subcostal vein,
 two breaks in the costal vein,
 a small anal cell in the wing,
 convergent postocellar bristles;
e.g. Drosophila pseudoobscura
4) Gastriphilidae: (e.g Bot flies)
a. Flies resemble with honey bees in general appearance
b. Mouth parts are vestigial(Non functioning)
c. Oral opening(Mouth cavity) of mouth is rounded and minute.
e.g Gasterophilus intestinalis

6. 5) Muscidae: (e.g House fly)
 Medium sized
 Gray coloured
 Red eyes
 Oral Opening and Mouth parts are normal.
e.g. Musca domestica
6) Oestridae: (e.g Warbal flies)
 Body is fuzzy with long dense hairs
 Oral opening(Mouth cavity) is small and triangular
 They are large, gray-brown flies.
e.g Oestrus ovis
7) Hippoboscidae: (e.g Forest fly)
 Ectoparasite of horse and many other Cattles
 Head is Sunkened into Thorax
 Antennae is inserted in depression
 Legs are short and stout
 Claws short and often toothed.
 E.g. Hippobosca equina