Dedicated to summarizing the facts regarding origins
Swainson Hawk Gallery
& Nature Photo Galleries
Mosasaurs Gallery
Mosasaur Clidastes[2]
Platecarpus Skeleton[1]
Mounted in the Paleontological Exhibit,
Walker Geological Museum, University of Chicago
Halisaurus Partial Jaw and Teeth in Matrix (fossil)
1809 Fd. phosphate mine near Khourigba, Morocco
8" max. dimension of matrix
Mosasaur Skull Views
Upper left - Clidastes from the side [3], lower left - Tylosaurus from the top [4],
upper right - Platecarpus from the top [5], and lower right - Platecarpus from below [6]
Mosasaurs were marine reptiles with generally long slender bodies propelled by two sets of paddles and a long tail. Their heads were tapered towards the front. They had two nostrils and like alligators and pleisosaurs, they needed to surface to breathe. The fossil record indicates that there were a number of kinds of mosasaurs. Mosasaur fossils have been found in North America, Europe and Africa. Evolutionary statements on mosasaurs are merely speculation.
Mosasaur Tylosaurus Carbonized Scales [7]
Scales are small for this size of reptile.
Mosasaur Paddle Bone and Tooth in Matrix (fossils)
1768 Fd. phosphorous beds in the Oulad-Abdoun Basin surrounded
by the Atlas Mountains near the town of Khouribhga, Morocco
4.8" max. dimension of matrix
Mosasaur Premaxilla (pm) with Other Fossils in Matrix
1768 Fd. Morocco
5.6" max. dimension matrix
Globbidens Tooth (fossil)
With small portion of root
1388 Fd. Atlas Mountains,
North Africa
Mosasaur Tooth (fossil)
Without root
1025 Fd. Morocco
Globidens alabamensis [8]
Part of mandible with teeth
Fd. Alabama, USA
Mosasaur Tooth (fossil)
Without root
1814 Fd. Big Brook, Marlboro, New Jersey, USA
Mosasaurus camperi [9]
Imperfect jaw and skull
Fd. Maestricht,Holland
Mosasaur Paddle Bones [10]
Left - Clidastes,left front paddle; middle - Tylosaurus, left front paddle; and right - Platecarpus, right front paddle
Copyright 2016 All rights reserved.
Clidastes propython Fossils [11] Plus three fossils of Tylosaurus at lower left corner (22-24)
Mosasaur Imperfect Caudal Vertebra[12]
Left - anterior view; right - left lateral view
Fd. Alabama
Mosasaur Imperfect Vertebra
Spinal cord channel is plugged and
portions of processes missing
1826 Fd. Sulfur River, Texas, USA
Mosasaur? Vertebra in Matrix (fossil)
1834 Fd. Sidi Chanan, Morroco
8.7" max. dimension of matrix



[1] Williston, Samuel, Water Reptiles of the Past and Present, (Chicago, IL: The University of Chicago Press, 1914),151

[2] Ibid., 147

[3] Ibid., 155

[4] Ibid.

[5] A Guide to Reptile Fossils and Fishes in the Department of Geology and Palaeontology in the British Museum (Natural History), (London: Harrison and Sons, 1896), 28

[6] Williston, 155

[8] Ibid., 167

[7] Ibid., 160

[8] Ibid., 167

[9] A Guide to Reptile Fossils and Fishes..., 29

[10] Williston, 157-158

[11] Cope, Edward, Synopsis of the Extinct Batrachia and Reptilla of North America, Part 1, (Philadelphia: McCalla and Stavely), Plate XII

[12] Lydekker, Richard, Catalogue of the Fossil Reptilla and Amphibia, Part 1, (London: Taylor and Francis, 1888), 269