Overview

Eggs are oblong-oval, minute (average 0.3-0.4 mm according to Shevchenko, 1929) and difficult to find in nature. Newly-laid eggs are soft, light yellow, with a shiny surface. After several hours they darken, become hard, dark brown and show characteristic thin ridges (Perfil'ev, 1968).
They are laid in cracks and crevices in moist ground, among leaf litter, between buttress roots of trees, at the bases of termite mounds, on stable floors and in poultry sheds, where adult flies rest and the microclimate is high.
The site and type of habitat is species-dependent. Between 10/15 and 100 eggs are laid in a single batch (40-70 usually in one oviposition cycle (WHO, 1990)).
Under optimum conditions they hatch in 6-17 days. Longer periods are necessary in cooler conditions.