In 1995 , 2008 and 2009 , three O. edmontonicus specimens with evidence of feathers were found ; two adults with quill knobs on the lower arm , indicating the former presence of pennaceous feather shafts , and a juvenile with impressions of up to five centimetres long primitive feathers in the form of hair-like filaments covering the rump , legs and neck .
In 1995 , 2008 and 2009 , three O. edmontonicus specimens with evidence of feathers were found .