Kingdom:   Animalia
Phylum:     Arthropoda
Class:        Insecta
Order:       Diptera
Suborder:   Brachycera
Infraorder: Tabanomorpha
Superfamily:       Tabanoidea
Family:      Tabanidae
Subfamily: Tabaninae
Tribe:        Tabanini
Genus:      Tabanus
Common names: Green Heads, March flies, Horseflies.

Greenhead flies are fast and agile and are the size of a honeybee with a body length of about 10mm. They have large compound eyes with reflective iridescent colour. Their wings always have the 'Y' shaped veins at the tip. Usually, there are the dense short hairs on their body. The tarsi (feet) have three pads instead of two.

Females of most species are anautogenous, meaning they require a blood meal before they are able to reproduce effectively. The females have large, sharp mouthparts beneath its head. Its saliva has anticoagulant properties and wounds inflicted by this fly tend to be large, painful and long-lasting. They habitually feed on mammalian blood and consequently diseases and parasites can be transmitted. Females live for three to four weeks and may lay about 100 to 200 eggs per blood meal.

The male flies are not ectoparasitic and lack mandibles, their eyes meet in the middle. They feed on nectar and pollen.

The larvae of most species live in fresh water, damp soil or rotting plants. They are carnivorous, preying on insects and snails.

Male. The eyes are together.
Fly Genus Tabanus.JPG

Male
Green head fly. Genus Tabanus.JPG

Female with eyes apart.
Greenhead female-001.JPG

Male
Fly Greenhead Tabamus male.JPG

Female
March flies Genus Tabanus .JPG

Thanks to Wikipedia for text and information: https://creativecommons.org/licenses/by-sa/3.0