Query: Prehistoric animals that are extinct mammals that are Hell Creek fauna
Domain: animals
Relevant documents:
Didelphodon
Nanocuris
Mesodma
Protungulatum
Cimolomys
Cimolestes
Protalphadon
Leptalestes
Paracimexomys
Cimexomys
Stygimys
Alphadon
Meniscoessus