Male horseflies feed on pollen and nectar, but the females suck blood as well and are common pests of animals and sometimes of humans. The bites of many species are very painful. The larger horseflies, e.g., the mourning horsefly and the 1-in. The deerflies, which carry the diseases anthrax and tularemia , and in Africa, a filarial worm infestation, belong to this group.
Horseflies are most abundant in hot weather.
The eggs are laid on plants or stones close to water. Horseflies are classified in the phylum Arthropoda , class Insecta, order Diptera, family Tabanidae. See insect . Listing from Electric Library , a pay service. No relevant pictures or maps found.