The poplar admiral (Limenitis populi) is a butterfly in the Limenitidine clade of the family Nymphalidae.
The wingspan in spread specimens varies for the males from 66 to 77 mm, and for the females from 82 to 85 mm, all mesures done on the larger private collection of Limenitis populi, now in the hands of Jean-Claude Weiss, the well-known specialist of Parnassius. In fact the specimens in the field are relatively of the same size, the difference in measures are mainly because some sub-species are larger or smaller than other ones, it does not mean the size of this species is so variable in one location. It exists some specimens very small, about half size, but they are issued from breedings. So it is a noticeable difference in size between genders. The females have distinct broad white lines over their back wings. On the males the lines are narrower and fainter, and sometimes are not there at all. The upper surface is dark brown with white spots. The white stripe is surrounded by orange and blue borders. The underside is orange.
Poplar Admiral habitat is widespread in continental Europe and many areas in Asia. The large, seldom-seen Poplar Admiral is one of the biggest butterflies in Europe. It is found in deciduous forests, where aspen (Populus tremula) or black poplar (Populus nigra) trees grow. This is because the caterpillar only eats the leaves of these species of tree. In altitude, for instance in the Alps, where there are not large Populus forests, they accommodate with a grove, in the southeast of France they can be seen flying in large open spaces, for instance in the department of Alpes-Maritimes, as noted by Jacques Rigout. The males are easier to find. The females are rarer, because they tend to stay in the tops of the trees and seldom venture to the ground (see above).
The species is known to occur in western Europe from Denmark to northern Italy (the Spanish record noted by Miguel-Angel Gomez Bustillo is doubtful), then Germany to Greece, Russia to Japan including China. Jacques Rigout has published precise distribution maps in France of this butterfly. The study was done by listing the data of the specimens preserved in the Paris Museum, those in the British Museum and the captures done by the French entomologists. The distribution since seems to be rather reduced (no more seen in Forêt de Mormal - North of France - the last 20 years where it was a relatively common species).
The now rare Poplar Admiral is a protected species. The species is endangered primarily due to the clearing of forests containing the trees that they must feed on to survive. Conifer species are more interesting financially to exploit.
