A common name for this species, mourning cloak, refers to its resemblance to a traditional cloak worn when one was mourning the death of a loved one. The scientific name is derived from both Latin and Greek; Latin: Nymphalis - of, or pertaining to a fountain, Greek: Antiopa - wife of Lycus, King of Thebes. It may appear in these photos that this butterfly only has four legs, but this is not the case - it has six, only the front pair are greatly reduced, appearing hairy and brush like. This is the reason members of this family, the Nymphalidae, are commonly known as "brush-footed butterflies".

The Mourning Cloak (Nymphalis antiopa) is a butterfly native to Eurasia and North America. The immature form of this species is sometimes known as the Spiny Elm Caterpillar. The Mourning Cloak has a wingspan of 62 - 75 mm. The upper side of the butterfly is colored in a very dark red, with a bright, yellowish border around the wings. There is a darker band with bright blue spots between the border and the dark red inner side.

Mourning Cloaks live in the Northern Hemisphere. In North America the species ranges from the northern tundra to central Mexico. It is also found throughout continental Europe to Eastern Siberia and Japan. The species is only rarely found in Great Britain. Its British common name, "Camberwell Beauty" came about when it was first discovered in Britain near Camberwell in the 1700s. It is a rare migrant there, and another old name was "Grand Surprise". The Mourning Cloak was adopted as the state butterfly of the State of Montana in 2001.