fossil tooth of mackerel shark Otodus obliquus (Agassiz, 1843) Late Paleocene - Early Eocene, from the phosphate mines near Khouribga, Morocco
Fossil tooth of Otodus obliquus (Agassiz, 1843) from the Late Paleocene-Early Eocene of the Khouribga Basin, Morocco
Otodus is a genus belonging to the shark group known as mackerel sharks. It first appeared in the Late Paleocene and was fairly common in the Early Eocene, a time range characterized by the warmest temperatures of the Cenozoic. This time period had two major spikes in temperatures, The Paleocene-Eocene Thermal Maximum (PETM) at around 55 million years ago and the Early Eocene Climactic Optimum (EECO) at 51-53 million years. The PETM is characterized by a rise in sea surface temperatures by as much as 8˚C in high latitudes, considerably less at the equator. Mid-latitude Atlantic sea surface temperatures ranged above 30˚C and possibly as high as 35˚C, influencing growth rates for Otodus, which were greater than for other megatoothed sharks across the PETM and EECO. As a comparison, sea surface temperatures of 35˚C were only reached in the Atlantic in the equatorial zone and not in the mid-latitudes in 2020.
The Khouribga Basin or Ouled Abdoun Basin is a sedimentary basin west of the Atlas Mountains. It is the largest of Morocco’s major phosphate basins, containing at least 26.8 billion tons of phosphate. It is an important site for marine vertebrate fossils. Otodus obliquus is a dominant species in the phosphate quarries and is known only from teeth and vertebrae, since the skeleton was cartilaginous and not bony, so was not fossilized. Characteristic of this species' teeth are the smooth edges, large size, and two small lateral cusps.
These are complete and are not repaired specimens. The coin is 2.2 cm in diameter for scale.
Select a specimen: You can select a specimen by telling us the page and letter of the specimen you would like us to pack.
Shipping: in a First Class package unless combined with other items. Click > Shipping < for shipping rates. Use back button to return to this page.
Making multiple purchases? Click on the "combine shipping" button in the shopping cart. We'll send an invoice with combined shipping. A link in that invoice will bring you back to checkout, no hassle.