El Doctor Formation
The El Doctor Formation is a geologic formation in Mexico. It preserves fossils dating back to the Albian and Cenomanian stages of the Cretaceous period. Ammonite fossils show that age of Late Albian is more likely.
Description
The light grey micritic limestone sequence with intercalated black chert lenses was deposited in an open marine basin with a hypersaline and/or poorly oxygenated bottom.Fossil content
The formation has provided the following fossils:;FishSqualicorax falcatusPtychodus decurrens
- RajiformesEnchodus zimapanensisXeneichthys yanesiHeckelichthys preopercularisMotlayoichthys sergioiNunaneichthys mexicanusIchthyotringa mexicanaMuhichthys cordobaiDalgoichthys tropicalisHanduichthys interopercularisPseudomonocentris microspinosusAraripichthys sp.Vinctifer sp.Pachyrhizodus sp.
- cf. Tselfatia
- Pycnodontiformes
- Cladocyclidae
- Elopiformes
- Gonorhynchiformes
- Mawsoniidae
- ''Palinurus sp.''
Ammonites
Mortoniceras sp.- Hamites aff. renziBeudanticeras sp.