In the X-ray style in Australian Aboriginal art, animals and human figures are depicted with bones and internal organs clearly visible. X-ray style paintings occur primarily in the caves and rock shelters in the western part of Arnhem Land in northern Australia. The style is thought to have developed around 2000 BCE. Web resource here.

Fish in X-ray style. Ubirr Rock Shelter, Kakadu National Park, Northern Territory, Australia. Photo: Michael Wifall.