A few nice extinct animals images I found:
the extinct papalo (or buffalo?)
Image by 10b travelling
A selection of petroglyphs from the Wadi Methkandoush (aka Wadi Matkhandouch) site in the Msak Settafet region of southern Libya.
This animal, related to the cow / buffalo apparently died out because its horns pointed forward, a design fault for a grazing animal...