The Small Copper, American Copper or the Common Copper, Lycaena phlaeas, is a butterfly of the Lycaenids or Blues family. It is a common and widespread little butterfly easily identifiable in the UK. (There are similar species in continental Europe.)
The upperside forewings are a bright orange with a dark outside edge border and with eight or nine black spots. The hindwings are dark with an orange border. Some females also have a row of blue spots inside the orange border and are known as form caeruleopunctata. The undersides are pattenered in a similar way but are paler. The black spots on the forewings are outlined in yellow and the dark colouring is replaced by a pale brownish, gray. The hindwings are the same brown/grey colour with small black dots and a narrow orange border. The caterpillars (larvae) are usually green, but some have a purple stripe down the middle of the back and along each side.
It is widespread and common across Europe, Asia and North America, and also found in North Africa south through Ethiopia.
It can be found almost anywhere in south/central England and Wales although never, it seems, in large numbers. Its distribution becomes more patchy in northern England, Scotland and Ireland. It is found in a wide variety range of habitats from chalk downlands, heathland, woodland clearings to churchyards and waste ground in cities.
In bright sun it is a very active little butterfly with the males setting up small territories which they will defend vigorously against rival males or indeed any unlucky passing insect. Even the shadow of a large bird passing overhead is enough to get him going. Females are pursued mercilessly and mating usually occurs low down in vegetation.
The eggs are laid singly on the underside of foodplant leaves and the young caterpillar feeds on the underside of the leaf creating "windows" by leaving the upper epidermis of the leaf untouched. Pupation takes place in the leaf litter and the pupa is thought to be tended by ants. There are between two and three broods a year, fewer further north. In exceptionally good years, a fourth brood sometimes occurs in the south and adults can still be seen flying into November. The species overwinters as a caterpillar.
Depending on the habitat, Common Sorrel (Rumex acetosa) and Sheep's Sorrel (Rumex acetosella) are the two main food-plants, although other Docks (Rumex spp.) are occasionally used.
Description taken from Wikipedia: http://en.wikipedia.org/wiki/Lycaena_phlaeas