Unknown Structures in Multituberculate Skull

Abstract

UP until now, no complete multituberculate skull has been known. Although skulls of two Palaeocene genera, Ptilodus Gidley and Taeniolabis Cope, are nearly complete, they both lack the lateral wall of the braincase and the occipital region¹. Large collections of Cretaceous multituberculates recovered recently in North America through application of underwater screening techniques have yielded isolated teeth and skull fragments^2–4. A collection of Cretaceous multituberculates has also been recovered from Bayn Dzak (Shabarakh Usu) in the Gobi Desert in Mongolia by the Polish-Mongolia palaeontological expeditions⁵. The Gobi collection is smaller than that from North America, but it is more complete, having some entire skulls associated with fragments of the postcranial skeletons^6,7. The age of the Bayn Dzak multituberculates is estimated as Coniacian or Santonian⁶.