Severn Formation

Severn Formation
Stratigraphic range: Maastrichtian PreꞒ Ꞓ O S D C P T J K Pg N
Type	Geological formation

The Severn Formation is a Mesozoic geologic formation in Maryland. Dinosaur remains diagnostic to the genus level are among the fossils that have been recovered from the formation. ^[1]

Paleofauna

Dinosaurs

• "Coelosaurus" antiquus ^[2]
• Ornithomimidae indet. ^[3]
• Hadrosauridae indet. ^{[2] [3]}

Plesiosaurs

• Cimoliasaurus magnus ^{[2] [3]}

Mosasaurs

• Halisaurus platyspondylus ^{[4] [2]}
• Prognathodon rapax ^[2]
• Mosasaurus hoffmanni ^[2]
• Mosasaurus sp. ^[3]
• cf. Mosasaurus conodon ^[2]
• Mosasauridae indet. ^[2]

Crocodylomorphs

• Deinosuchus rugosus ^[3]
• Thoracosaurus neocesariensis ^[2]
• Alligatorinae indet. ^[3]

Turtles

• Peritresius ornatus ^{[2] [3]}
• Osteopygis emarginatus ^[2]
• Trionyx priscus ^{[2] [3]}
• Toxochelyidae indet. ^[2]

Chondrichthyans

• Carcharias holmdelensis ^[3]
• Carcharias samhammeri ^[3]
• Chiloscyllium greeni ^[3]
• Cretalamana appendiculata ^[3]
• Dasyatis sp. ^[3]
• Tomewingia problematica ^[3]
• Galeorhinus garadoti ^[3]
• Ginglymostoma sp. ^[3]
• Heterodontus sp. ^[3]
• Hybodus sp. ^[3]
• Ischyrhiza cf. avonicola ^[3]
• Ischyrhiza mira ^[3]
• Myliobatis sp. ^[3]
• Odontaspis aculeatus ^[3]
• Plicatoscyllium antiquum ^[3]
• Plicatoscyllium derameei ^[3]
• Pseudohypolophus mcnultyi ^[3]
• Ptychotrygon vermiculata ^[3]
• Raja farishi ^[3]
• Rhinobatos sp. ^[3]
• Rhombodus binkhorsti ^[3]
• Serratolamna serrata ^[3]
• Squalicorax kaupi ^[3]
• Squalicorax pristodontus ^[3]
• Squatina hassei ^[3]
• Ischyodus sp. ^[3]

Osteichthyans

• Albuidae indet. ^[3]
• Anomoedus cf. haseolus ^[3]
• Cylinadracanthus sp. ^[3]
• Egertonia sp. ^[3]
• Enchodus ferox ^[3]
• Hadrodus sp. ^[3]
• Lepidosteus sp. ^[3]
• Paralbula casei ^[3]

See also

• Earth sciences portal
• Paleontology portal
• Dinosaurs portal

• List of dinosaur-bearing rock formations
  • List of stratigraphic units with few dinosaur genera

Footnotes

1. Weishampel, et al. (2004). "Dinosaur distribution." Pp. 517-607.
2. Baird, Donald (1986). "Upper Cretaceous Reptiles from the Severn Formation of Maryland". The Mosasaur. 3: 63–85.
3. Hartstien, Eugene F; Decina, Lawrence E; Keil, Ronald F (1999). "A Late Cretaceous (Severn Formation) Vertebrate Assemblage from Bowie, Maryland". The Mosasaur. 6: 17–23.
4. Holmes, Robert B.; Sues, Hans-Dieter (2000). "A Partial Skeleton of the Basal Mosasaur Halisaurus platyspondylus from the Severn Formation (Upper Cretaceous: Maastrichtian) of Maryland". Journal of Paleontology. 74 (2): 309–316. JSTOR   1306908.

References

• Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. 861 pp.  ISBN   0-520-24209-2.