The Pen Formation is a Campanian-age geologic unit in the western United States.

Vertebrate fauna

Sharks are well known from the Pen Formation.[1]

Other fishes include Xiphactinus,[1] the ray Ptychotrygon,[1] and gar.[1] The nodosaurid ankylosaurs Acantholipan and CPC 273 have also been found in the Pen Formation.[2]

Footnotes

  1. ^ a b c d e f g h i j k "Big Bend National Park," Hunt, Santucci, and Kenworthy (2006); page 65.
  2. ^ Héctor E. Rivera-Sylva; Eberhard Frey; Wolfgang Stinnesbeck; Gerardo Carbot-Chanona; Iván E. Sanchez-Uribe; José Rubén Guzmán-Gutiérrez (2018). "Paleodiversity of Late Cretaceous Ankylosauria from Mexico and their phylogenetic significance". Swiss Journal of Palaeontology. in press. doi:10.1007/s13358-018-0153-1.

References

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