Hipparchia fagi, the woodland grayling, is a butterfly of the family Nymphalidae.[1]
The Latin species name fagi, meaning of "beech" (=fagus), refers to the prevailing species of trees in the relating biotope.
This widespread European endemic species can be found in most of Europe, mainly south of the Alps (Albania; Andorra; Austria; Bosnia and Herzegovina; Bulgaria; Croatia; Czech Republic; France; Germany; Greece; Hungary; Italy; Macedonia; Montenegro; Portugal; Romania; Russia; Serbia; Slovakia; Slovenia; Spain; Switzerland; Ukraine).[2] It occurs on broad-leaved deciduous forests, coniferous woodland, grassy vegetation, in woodland glades and woodland rides and, from sea level to 1,600 m elevation.[3]
Hipparchia fagi has a wingspan of 66-.[4] These large butterflies have dark brown uppersides of the wings, with a fringed margin, a white submarginal band more evident in the females and one black eyelet at the apex of each forewings. In the males the white band has a single very small eyelet on each hindwing, sometimes showing a white pupil, while in the females it shows one or two ocelli.[5]
The underside of the forewings is rather similar to the upperside: The hindwings are marbled of brown and white with a broad white band. The white band on the internal edge of the underside hindwings is curved, while the white band on the underside forewings is often without a significant indent.[6]
The colouration and pattern of these butterflies are an excellent camouflage on the bark of the trunks where the butterfly usually rests, with the eyespots hidden by the closed wings.[3] This species is similar but larger than Hipparchia hermione. It is also rather similar to Hipparchia syriaca and Hipparchia genava.
The caterpillar has a pale brown head with four darker streaks. Body is light brown with a bifid posterior end, a dark brown dorsal band and brownish lateral bands.[7]
Adults fly from June to September.[4] This species has one generation a year. The caterpillars overwinter. The larvae feed on various types of grass, such as Brachypodium pinnatum, Bromus erectus, Festuca rubra, Holcus lanatus and Holcus mollis.[3]