 An <unk> ( ankle bone ) thought to belong to a species of Allosaurus was found at Cape Paterson , Victoria in Early Cretaceous beds in southeastern Australia . It was thought to provide evidence that Australia was a <unk> for animals that had gone extinct elsewhere . This identification was challenged by Samuel Welles , who thought it more resembled that of an <unk> , but the original authors defended their identification . With fifteen years of new specimens and research to look at , Daniel Chure <unk> the bone and found that it was not Allosaurus , but could represent an <unk> . Similarly , <unk> <unk> and Phil <unk> , in their description of <unk> , noted that the bone closely resembled that of their new genus . This specimen is sometimes referred to as " Allosaurus <unk> " , an informal museum name . It may have belonged to something similar to , or the same as , <unk> , or it may represent an <unk> . A speculative " polar " or " dwarf allosaur " was used for the " Spirits of the Ice Forest " episode of Walking with Dinosaurs . 
