The Common Brimstone has a wing span of 54-64 cm. When it is resting both sexes are easily recognizable because of the wing shape. During flight the male is easy to know because of the lemon yellow colour, while the female reminds about a Large White butterfly.
The middle spots varie a little in size and colour, but else are almost no variations. Flying time is July-October and again after overwintering in March-June. It is one of the earliest butterflies of the year. Usually it shows in the first sunny days, when the temperature is above 10 degrees (Celsius). It can live almost one year as an adult butterfly.
The brimstone overwinters as adult butterfly among branches and leaves. The fodderplants are alder buckthorn and common buckthorn. Its habitat is forest and thicket with alder buckthorn and common buckthorn The brimstone is roaming and is often seen in open flowerrich terrain, like in lucerne fields, where the species seek nectare before overwintering.
The brimstone is very "seeking" to flowers, both spring and autumn. In late summer it seeks especially the Asteraceae-family, like cabbage-thistle and other thistles - and to red clover and lucerne, or to the buddleias in the gardens.The species is seen on the first sunny days of the year where the temperature reaches 8-10 degrees Celsius. It flies unsteady and low, and in early spring it is often sitting upon sunny spots in the forest floor to get some warmth.
Frequency and spread:
Common Brimstone lives in Europe, North Africa and Asia; across much of its range it is the only species of its genus and is therefore simply known ad "The Brimstone"
The brimstone is very common in Denmark, especially in and around moist thicket-woods. It is rather scarce in West Jutland. The frequency varies from year to year, and the species might roam far and wide and reach even small islands with no permanent living conditions.
Source: Michael Stoltze. Dagsommerfugle i Danmark, 1998.
text and photo: grethe bachmann