Phylum Arthropoda, Class Insecta, Order Diptera

Question 1

What is the common name for the family Ceratopogonidae?

Answer 1

Biting midges

Question 2

What is the general features of the genus Culicoides?

Answer 2

Small flies with short mouthparts
The antennae of females are long and pilose (hair-like)
The thorax is humped over a small head with indentations
Contains spotted wings

Females feeds on blood to produce eggs, otherwise they feed on nectar

Question 3

What is the general lifecycle of the Genus Culicoides?

Answer 3

Holometabolous development

Egg–> larva –> pupae –> adults

Question 4

What is the species of Culicoides that causes the ‘Queensland itch’

Answer 4

Culicoides brevitarsis

Question 5

What is the general pathology that Culicoides brevitarsis causes?

Answer 5

Causes Queensland itch which is a hypersensitivity reaction

Intense puritis, crusting, skin thickening.

Question 6

WHat are the two subfamilies of the Familt Muscidae?

Answer 6

Subfamily Muscinae
- Sucking / lapping, have enzymes

Subfamily Stomoxinae
- Feed on blood

Question 7

What are the general features of Haematobia exingua?

Answer 7

Host - cattle, buffaloes, humans

Known as the Buffalo fly

Both sexes feed on blood and are pool feeders

Permanently associated with the host - feeds many times a day with bits that are painful.

Maxillary palps are longer than half the length of the proboscis
Proboscis ends with teeth - causes lesions and pools blood.
Labella has sharp teeth
Eyes are large, red.

Question 8

What is the lifecycle of Haematobia exigua

Answer 8

Holometabolous development

eggs–> larva –> pupa –> adults

Females require blood meals for egg production

Females leave the host to lay eggs in the fresh faeces of cattle –> larvae, pupae within the faeces

Lifecycle can be as short as 9-11 days

Question 9

Define Myiasis

Answer 9

Is the infestation of the organs / tissues of host animals by the larval stages of dipterous flies

Are maggots / grubs

Question 10

What is the structure of the larvae?

Answer 10

Conical, pointed anteriorly and truncated posteriorly

Body is segmented

Mouth contains hooks

Respiration through spiracles - anterior (2nd segment) and posterior (12th segment)

Posterior spiracles contain spiricular plates. The respiratory openings are present for gas exchange. The outer rim of the spiricular plate is called the peritreme.

Button - is a rounded structure that either lies in the opening of the the peritreme, surrounded by it or completely within its margins.

Question 11

What are the types of Myiasis classification?

Answer 11

Obligatory –> specific

Facultative –> develop on living and dead organic matter.

• Primary fly strikes: initiates myiasis
• Secondary fly strikes: unable to initiate but can occur/invade and extend lesions made by the primary flies
• Teritary fly strikes: feed on the surface of the strike wound but do not extend the wound.

Accidental myiasis: when eggs / larvae are accidentally swallowed –> vomiting and diarrhoea

Question 12

What is the general features of Lucilia cuprina?

Answer 12

Is apart of the Family calliphoridae (blowflies)

Located in warm, temperate and subtropical areas

Is responsible for over 90% of the flystrikes in Australia (sheep mainly). Is an introduced species

Contain the metalic blue/ green tinge on body with red eyes.

Question 13

What is the lifecycle of Lucilia cuprina?

Answer 13

Female flies need a protein meal and to mate before they can produce eggs

Females can lay up to 250 eggs in a single mass on susceptible sheep

Are attracted to fleece rot and soiled fleeces (smell)

Eggs are laid in the afternoons and hatch in 8-12 hours (at night). Moisture is essential

First stage Larvae move to the skin and feed on protein rich exudate (from the skin because of the fleece rot)

Second stage larvae penetrate the skin and feed on tissues

Third stage larva mature in 2-19 days.

Drop to ground at night, burrow into the soil and enters forms into pupa or overwinter as pupa if temp is less than 15 degrees.

Emerging females need a protein meal to produce eggs

Question 14

What are the features of Lucilia cuprina L3 stage?

Answer 14

Body is white / creamy colour –> about 10-14mm

Does not contain accessory sclerites

Posterior spiracles are present with complete (full circle) peritremes, 3 slits.

Question 15

What is the general features of the Family Oestridae?

Answer 15

Commonly known as Bot flies

all species are parasitic within the larval stages.

Adults are bee - like flies with small eyes.

main issues in horses where the larvae enter into the stomach. In cattle, they enter in the subcutaneous tissues

Question 16

What are the general features of Gasterophilus species (bot flies)

Answer 16

Host - Horses
Larval stages located in the mouth (L1-2), stomach (L2-3) and rectum (L3)

In humans, they are located in the eye, skin, etc.

The most important species in Aus. are the Gasterophilus intestinalis,
Gasterophilus nasalis,
Gasterophilus haemorrhoidalis

L3 stage

• Reddish orange colour
• Fusiform and cylindrical shape
• Mouth contains cooks, is rhobust and is laterally directed.
• Contains a single or double row of spines which encircle the body segments

Question 17

What is the general lifecycle of the Gasterophilus species?

Answer 17

Holometabolous development
Egg–> larva –> pupa –> adults

Larva develop within the host.

Females lay eggs on the host –> larvae form within the eggs –> hatch –> larvae reach the mouth –> move into the stomach –> stay for 8-10 months –> detach and shed in the faeces –> larvae burrow into soil and form into pupae –> adults emergy

Question 18

What are the general features of G. intestinalis, G. nasalis and G. haemorrhoidalis

Answer 18

Gasterophilis nasalis –> contains 1 row of spines

Gasterophilis intestinalis –> contains 2 rows of spines. Have a mouth that contains hooks with a saddle-like depression

Gasterophilis haemorrhoidalis –> contains 2 rows of hooks which are uniform

Question 19

What are the general features of Oestrus ovis?

Answer 19

Hosts - sheep, goats
Larvae develop within the nasal passages and in the head sinuses

The L3 stage

• Ventral surface = flat, contain rows of spines on each segment
• Dorsal surface = convex with dark transverse bands
• Mouth hooks are well developed
• Posterior spiracles are brown and pentagonal shape.

Question 20

What is the lifecycle of Oestrus Ovis?

Answer 20

Females deposit LARVAE around nostrils
L1s crawl into the nasal cavity and then move into the sinuses where they molt to L2 and L3

L3 return to the nasal cavity and are sneezed out

Enter environment and the larvae burrow into the ground to form pupae then adults

The female flies can also deposit larvae in the eyes and nostrils of humans.

Question 21

What is the general features of the Hypoderma species?

Answer 21

Called Warble flies / Cattle grubs

Hosts are cattle and deer

Larval stages are located in the spinal canal, submucosa of the oesophagus and the subcut tissues.

The larvae will emerge through the skin

L3 stage:

• Ventral surface =concave
• Dorsal surface = convex
• each segment bears a number of tubercles and small spines
• The mouth - hooks are Small
• Posterior spiracles are kidney shaped. (not complete circle)

Question 22

What is the lifecycle of the Hypoderma species?

Answer 22

the female flies lay eggs on the hairs of the host

L1s hatch and migrate to the epidural fat of the spinal canal (Hypoderma bovis) or the submucosa of the oesophagus (Hypoderma lineatum).

The larvae leave their respective spors and migrate to the skin on the back of the cattle - causes a small swelling and hole.

The L3s leave the host through the hole in the skin, fall onto the ground and pupate.