Drosophila mettleri

Drosophila metlerri, commonly known as the Sonoran Desert fly, is a fly in the genus Drosophila. The species is found in North America and is most concentrated along the southern coast of California and in Mexico. D. mettleri are dependent on plant hosts, namely, the saguaro and cardon cacti. Thus, they are most prevalent in arid, desert conditions.^[1] It is able to detoxify chemicals found in the rotting liquid of cacti hosts, which allows it to use otherwise lethal soil as a nesting site.

D. mettleri was discovered in San Felipe, Baja California in October 1961 during an experiment where banana was used to attract several species of Drosophila.^[2] Due to physical geographic barriers between Sonoran Desert flies, gene flow explains speciation.

It breeds in soil moistened by liquid excreted by rotting cacti and on necrotic patches. The liquid found in rotting cacti patches serves as a nutrient source for D. mettleri larvae, despite it containing chemicals toxic to the intestines of other Dipterans.^[3] Several aspects of the fly species' courtship behavior, such as its courtship song and copulatory plugs, explain sexual selection methods in this fly.