fauna (n.)

1771, "the total of the animal life of a certain region or time, from Late Latin Fauna, a rustic Roman fertility goddess who was wife, sister, or daughter (or some combination) of Faunus (see faun).

Popularized by Linnaeus, who adopted it as a companion word to flora and used it in the title of his 1746 catalogue of the animals of Sweden, "Fauna Suecica." First used in English by Gilbert White (1720-1793) the parson-naturalist.