Pen Formation

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

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

• Lissodus selachos^[1]
• Squalicorax kaupi^[1]
• Cretorectolobus olsoni^[1]
• Ischyrhiza mira^[1]
• Scapanorhynchus texanus^[1]
• S. raphiodon^[1]
• Lamna appendiculata^[1]

Other fishes include Xiphactinus,^[1] the ray Ptychotrygon,^[1] and

gar.^[1]

Footnotes

1. ↑ 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 1.10 "Big Bend National Park," Hunt, Santucci, and Kenworthy (2006); page 65.

References

• Hunt, ReBecca K., Vincent L. Santucci and Jason Kenworthy. 2006. "A preliminary inventory of fossil fish from National Park Service units." in S.G. Lucas, J.A. Spielmann, P.M. Hester, J.P. Kenworthy, and V.L. Santucci (ed.s), Fossils from Federal Lands. New Mexico Museum of Natural History and Science Bulletin 34, pp. 63–69.