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.El Doctor Formation at Fossilworks.org 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:Feldmann et al., 2007 Fish Squalicorax falcatus Ptychodus decurrens Rajiformes Enchodus zimapanensisFielitz & González Rodríguez, 2010 Xeneichthys yanesi Heckelichthys preopercularis Motlayoichthys sergioi Nunaneichthys mexicanus Ichthyotringa mexicana Muhichthys cordobai Dalgoichthys tropicalis Handuichthys interopercularis Pseudomonocentris microspinosus Araripichthys sp. Vinctifer sp. Pachyrhizodus sp. cf. Tselfatia Pycnodontiformes Cladocyclidae Elopiformes Gonorhynchiformes Mawsoniidae Arthropods Aeger hidalguensis Polzia eldoctorensisHegna et al., 2014 Victoriacaris muhiensis Palinurus sp.
Ammonites
Mortoniceras sp. Hamites aff. renzi Beudanticeras sp.
Echinoderms
Echinoidea Crinoidea
See also List of fossiliferous stratigraphic units in Mexico Sierra Madre Formation
References
Bibliography