''Gasterophilus haemorrhoidalis'' (also called nose botfly or lip botfly) is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

of the

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

'' Gasterophilus'' that lays eggs on the lips and around the mouth of

horse The horse (''Equus ferus caballus'') is a domesticated, one-toed, hoofed mammal. It belongs to the taxonomic family Equidae and is one of two extant subspecies of ''Equus ferus''. The horse has evolved over the past 45 to 55 million yea ...

s, mules and donkeys. In

Equidae Equidae (sometimes known as the horse family) is the taxonomic family of horses and related animals, including the extant horses, asses, and zebras, and many other species known only from fossils. All extant species are in the genus '' Equus'', ...

, third-stage larvae attach to the stomach, but also to the rectum, sometimes in great numbers.Johannes Kaufmann, Parasitic Infections of Domestic Animals, Birkhäuser Verlag, Basel, Boston, Berlin, 1996, . Heavy infestation can cause anal

prolapse In medicine, prolapse is a condition in which organs fall down or slip out of place. It is used for organs protruding through the vagina, rectum, or for the misalignment of the valves of the heart. A spinal disc herniation is also sometimes ca ...

in foals and mules. They do not

parasitise Parasitism is a close relationship between species, where one organism, the parasite, lives on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The entomologist E. O. Wilson has ...

humans.

References

External links

GNWT - Environment and Natural Resources 'Nose Bot' page
Oestridae Parasitic flies Insects described in 1758 Taxa named by Carl Linnaeus {{parasitic insect-stub