Superficially similar to the Gatekeeper (Pyronia tythonus), the silvery mottled underside of the hindwing of the Southern Gatekeeper is a helpful identifying feature. The Gatekeeper has pale spots on the underside of its hindwings, whereas the Southern Gatekeeper does not.
This specimen was photographed in the Algarve region of Portugal. (Picture: Rob Petley-Jones)
Determining the gender of a Southern Gatekeeper is not difficult if you can view it from above it with its wings open. The male has rectangular sex brands comprising scent-producing scales, known as androconia, on its forewings. Where veins cross thes dark patches they are narrowly bordered in the orange background colour, which is not the case with the Gatekeeper, Pyronia tithonus. The female Souther Gatekeeper has no dark patches on its forewings and is therefore evidently much more of an orange butterfly.
Unlike many 'browns', the Southern Gatekeeper often rests with its wings open, which is very helpful when you are trying to determine the gender of any kind of Gatekeeper. Males, with their wingspan typically 3.5cm, are slightly smaller than females, which usually have a wingspan of about 4cm.
Southern Gatekeepers are found in southern Europe (Portugal, Spain, Italy and the southern half of France; it also occurs in the northern countries of Africa.
The larval foodplants of the Southern Gatekeeper are various grasses.