What Bug Is That? The guide to Australian insect families.

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A family of greatly modified ectoparasites on mammals and birds. There are some 24 described species in Australia, but some remain undescribed. Most fall in the large family Ornithomyinae, and more than 50% are introduced. The latter include the so-called 'sheep tick', Melophagus ovinus (L.), which can cause losses through anaemia and staining of the wool.

All species are blood-sucking ectoparasites. Adults live amongst the hair of mammals or the feathers of birds; in Australia most infest birds, but four species of Ortholfersia and one of Austrolfersis live on wallabies; M. ovinus on sheep; and Hippobosca equina L. on horses. Eggs develop within the body of the female fly and, when mature, are deposited away from the host (except in M. ovinus , where they are laid and pupate in the host's wool). This family contains wingless species.


Adult morphology is strongly adapted to life on the host: the body flattened, the mouthparts porrect (directed forwards), and the legs long and robust with large claws for grasping the host's hair or feathers. The general appearance is louse- or tick-like. With the exception of Melophagus , all Australian species are winged and the venation is characteristic, with the strong veins all concentrated anteriorly.


Many species have wide, cosmopolitan distributions - especially the parasites of sea-birds, with their wide-ranging hosts. Endemic Australian species are recorded mainly from the eastern states, including Tasmania.

  • Icosta sp.