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THE HOUSE FLY(Musca domestica)

Classification

Kingdom : Animalia

Phylum : Arthropoda

Class : Insecta

Order : Diptera

Family : Muscidae

Genus : Musca

Species : domestica

Scientific name is Musca domestica.

Characteristics of order Diptera

  • They have a pair of wings
  • the second pair of wings (hind wings) form halters or balancers
  • Antennae are short
  • mouth parts are after suctorial and sometimes piercing too
  • the cerci are too reduced or absent
  • metamorphosis is complete
  • many are important vectors

Examples of members in the order include mosquitoes, housefly, tsetse fly etc

Habitat

House flies live in filthy or dirty places such as toilets, dust bins, manure heaps, e.t.c.

External features

The body of the housefly is divided into three main parts, head, thorax and abdomen.

THE HOUSE FLY

The head

  • The head bears three simple eyes (ocelli) arranged in triangle and on each side is a large or prominent compound eye.
  • The antennae are short with three joints with last having spine hair.
  • The labium (upper lip) is modified into proboscis for sucking, which is expanded at the distal end to form a funnel shape.
liblum

Life cycle of a housefly

The housefly undergoes complete metamorphosis.

After mating, the female housefly lays eggs in batches. The eggs are laid on rotting matter such as meat or faeces, where it is warm and moist. This provides the conditions for the eggs to develop.After about 8-24 hours, the eggs hatch into larvae. The larvae (maggots) are white and conical shaped. The maggot has a small head which is not easily visible. The head bears a mouth with two hook-like teeth. These are used for feeding on decaying matter in which the larva finds itself. The hook-like teeth also helps the larva move through the decaying matter. The larva has no legs but has pads with short spines that help in movement. Spiracles are present only on the 2ndand the last segment. They are used for breathing. The larva has no eyes but sensitive to light. It prefers dark, moist, and warmer regions of the decaying matter. It grows by shading its outer layer (cuticle). After 5 days and shading its cuticle twice,the larva is about 1cm long. It then moves to a drier region of the meat or faeces and pupates.The pupa is cigar shaped. The cuticle hardens, darkens and becomes brown to form the puparium or pupa case. This forms a protective covering as internal reorganization of tissues takes place inside.After the puparium bursts open, the adult fly emerges. The wings expand and harden and after a few hours, the fly flies away

THE HOUSE FLY

Economic importance of house flies

  • They feed on faeces and manure heaps, hence help ingarbage disposal.
  • They are vectors of diseases i.e. spread or transmit diseases such as dysentery, cholera, red eyes, trachoma, etc.
  • It is a source of food for some organisms such as chameleons.
  • They are specimens for study purposes.

Control of house flies and prevention of diseases they spread

  • Spraying with an insecticide such as pyrethrum to kill the adult.
  • Proper disposal of faeces in latrines with covers, so that flies cannot get to the waste to lay eggs.
  • Washing hands with soap and clean water after visiting the latrine and before eating or preparing food.
  • Disposing of wastes in such a way that flies cannot reach them. E.g. burning or burying them.
  • Covering or storing food properly so that flies cannot settle on it.