Nectar drinkers whose females need blood for eggs
Tabanidae—horse flies and deer flies—are agile daytime biters on every continent save polar wastes and some islands. Males sip nectar with weak mouthparts; females wield paired cutting blades and a sponge to drink blood proteins before they can lay eggs.
Aeschylus already cast a relentless gadfly as Io’s torment in Prometheus Bound; Socrates later claimed the same insect as a metaphor for philosophical stinging. Pliny recorded Tabanus; rural English lumped tormentors as gad-flies from a word for spike, while cleg and gleg likely arrived via Old Norse. Chrysopsinae are the banded deer flies; stouter Tabaninae are the classic horse flies. Linnaeus named Tabanus in 1758; Meigen added Chrysops in 1802 and Haematopota, “blood-drinker.”
Bodies run about five to twenty-five millimetres, with the largest wingspans near sixty millimetres. Living eyes blaze with patterns that fade in cabinets; females’ eyes are widely separated, males’ nearly touch, and polarization vision helps females lock onto hosts. Roughly 4,455 species are described worldwide across Tabanoidea. Fossils reach the Early Cretaceous, with Eotabanoid wings from Berriasian Purbeck England about 145–140 million years ago. Larvae hide moist soils with Graber's organ at the tail tip.
Both sexes take nectar, and some Pangoniinae with extreme proboscises pollinate deep South African and Asian flowers such as Lapeirousia. Most females are anautogenous: after digesting a blood meal for about six days they hunt another host. That feeding habit can move equine infectious anaemia, trypanosomes, Loa loa, anthrax, and tularemia between animals and slash cattle weight gain and milk yield when shade is scarce. Greenland, Iceland, and Hawaii lack them entirely; Haematopota also skips Australia and South America.
Source: Tabanidae
