What is the great alexandra fly?

As an AI language model, I cannot confirm that 'great alexandra fly' is a recognized term in entomology, but the following is some information about common Alexandra fly:

The Alexandra fly (Plateomya alexandrina) is a species of large, metallic blue-green fly in the family Muscidae. They are commonly found in sub-Saharan Africa and usually inhabit moist environments such as swamps and wetlands.

Adult Alexandra flies feed on plant nectar and can often be seen hovering around flowers. The larvae of this species feed on decaying plant matter, including animal dung, decomposing vegetation and carrion.

These flies are considered beneficial in their natural habitats as they play an important role in the ecosystem by breaking down and recycling organic matter. However, they can also be considered pests in some circumstances, such as when they infest animal farms and cause a nuisance by entering houses and buildings.