Stomoxys calcitrans

Introduction

Stomoxys calcitrans (Image sourced from Skoch3, Wikimedia Commons)

Also known as:

Stable fly

S. calcitrans can feed on a number of hosts in close succession, and therefore can act as an important mechanical vector in the transmission of disease.

Identification

Stomoxys calcitrans has a high resemblance to Musca domestica. S. calcitrans is 5-7mm long, and both the males and females suck blood. They are grey with four long longitudinal stripes on the thorax, and with large black spots on the abdomen.

The larvae are identified bu examination of the posterior spiracles.

Life cycle

• Eggs laid on rotting hay and straw

• Larvae feed on vegetable matter

• Life cycle takes 1 month

• Adult flies survive for 1 month

Pathogenesis

• Production losses
  • Reduced weight gain
  • Milk yield losses
    • Up to 20% in cattle affected by fly worry

• Vectors for the retrovirus Equine infectious anaemia

• Mechanical vectors for protozoa e.g. trypanosomes in warmer countries

• Intermediate hosts of the nematode Habronema