The Fawn-breasted Brilliant is a hummingbird species native to South America, specifically found in Bolivia, Colombia, Ecuador, and Peru. This bird is particularly notable for its iridescent copper underparts, green above with areas of fawn, green, and copper spotting. It has a long, slightly curved beak, which is characteristic of many hummingbirds. There are three subspecies of the Fawn-breasted Brilliant, each occupying different slopes of the Andes Mountains: Heliodoxa rubinoides aequatorialis in Colombia and Ecuador (western slope), Heliodoxa rubinoides cervinigularis in Ecuador and Peru (eastern slope), and Heliodoxa rubinoides rubinoides in Colombia (central and eastern Andes)​​​​​​​​​​. The Fawn-breasted Brilliant resides in tropical forests and is somewhat uncommon with a patchy distribution. However, it is classified as a species of "least concern" by the International Union for Conservation of Nature. The diet of this hummingbird mainly consists of nectar, which it defends from other nectarivores, including insects like bumblebees. It exhibits an impressive feeding behavior, where it hovers before the flower or hangs from it, inserting its tongue up to 13 times per second. The bird also consumes small insects and spiders for extra protein, and the female especially catches large quantities of insects during breeding since they are an important food source for the chicks. The Fawn-breasted Brilliant catches insect prey by hawking, picking them from plants, and plucking them from spider webs​​​​.