Catocala is a generally Holarctic genus of moths in the family Erebidae. The genus was erected by Franz von Paula Schrank in 1802. The moths are commonly known as underwing moths or simply underwings. These terms are sometimes used for a few related moths, but usually – especially when used in plural, not as part of a species name – they are used to refer to Catocala only. Of the more than 250 known species, slightly less than half are found in North America – mostly in the United States – while the rest occur in Eurasia. About one-fifth (almost 30) of these species are native to Europe. A few species occur in the northern Neotropics and Indomalaya. Description and ecology Most species of Catocala have medium to large adults, cryptically coloured except for the hindwings, which are marked with stripes in orange, red, white, or even blue. In some, the hindwings are mostly blackish. Unlike what the common name "underwings" seems to suggest, the colour is brightest on the upperside. However, the bright hindwings are not visible at rest, being hidden under the dull forewings – hence the name. Due to their diversity and variety of colors and patterns, underwing moths are popular with collectors of Lepidoptera. In, The Fauna of British India, Including Ceylon and Burma: Moths Volume II, the genus described as follows. It is believed that the bright colors, arranged in usually roughly concentric markings, at a casual glance resemble the eyes of a predatory animal, such as a cat. An underwing moth, well camouflaged in its daytime resting spot on a tree trunk or branch, will suddenly flash open the hindwings when disturbed. A bird or other small predator that is not used to this display is likely to be frightened, allowing the moth to escape. However, unlike some other bright-colored moths which are bad-tasting or even poisonous to predators, underwing moths are well palatable at least to some birds (e.g. the blue jay, Cyanocitta cristata). To assist in avoiding nocturnal predators such as bats, these moths also possess (like many of their relatives) fairly well-developed hearing organs. The caterpillars of most species feed on the leaves of woody plants, usually trees but sometimes shrubs. Typical food plants are Fagales of the families Betulaceae, Fagaceae and Juglandaceae – mainly hickory (Carya), oak (Quercus) and walnut tree (Juglans) species, as well as others such as alder