In this post, I will share some of my whale finds from the late Oligocene Chandler Bridge formation from the Summerville, SC area (Chattian age – 27.5 Ma). The Chandler Bridge along with the underlying Ashley formation (Rupelian age – 29.2 Ma) make up the richest deposit of Oligocene marine vertebrates ever described. As I noted in my previous post, this fauna includes (in addition to the fantastic cetaceans) birds, crocodilians, turtles, sirenians, fishes, and an abundance of the teeth and dermal denticles of sharks and rays.
At least five different genera of odontocetes have been described from these beds, including a new species of the very primitive genus Xenorophus, a new species of Squalodon, and 3 totally new genera. I am still waiting to get the published descriptions of these new genera. In all, between the Chandler Bridge and the Ashley formation, 25 new species of cetaceans have been described from South Carolina. Besides the odontocetes, there have also been 3 new species of mysticetes (suborder Mysticeti), and at least 2 new species of archeocetes (extinct suborder Archeoceti). The previous latest known occurrence of archeocetes was from the mid to late Rupelian (middle Oligocene).
In the attached photos you can see various elements of the post cranial skeleton of some of the “primitive” Oligocene toothed whales (suborder Odontoceti, super-family Squalodontoidea) from the ChB. Most all of my skull material was donated to the Charleston Museum for their research into these animals, especially involving cranial “telescoping” (the movement of the nasal openings to the apex of the skull) and how it relates to the evolution of the odontocetes. The Oligocene is widely regarded as the period when these “primitive” whales were completing their evolution into the ‘modern’ forms of today. The sheer number and the excellent preservation of the ChB whales are allowing scientists to witness this evolution as it occurred in the mid and late Oligocene.
The first photo includes a section of the left mandible, two specimens of the tympanic bullae (back of picture), a beautiful and complete atlas vertebra, a cervical vertebra, 3 thoracic vertebrae and 2 rib sections. The second photo is a close-up of the cervical. The next photo shows some of the lower vertebrae. Photo 4 shows a close-up of one of these vertebrae which I removed from in situ in bed 2, with the neural arch (for the spinal cord) and the wing-like transverse processes still intact. Photo 5 is a group of loose teeth I have found over the years. Photo 6 is a close-up of the mandible fragment with 2 of the double-rooted molars still in place. Photos 7 & 8 are molars. Photo 9 is a pre-molar, and
photo 10 is an incisor.
Latest posts by Sammy Peek (see all)
- A Protocetid Whale from South Carolina - October 19, 2016
- Fossil Hunting in the Whitewater Formation, March 19, 2016 - March 25, 2016
- Fossil Hunting in Summerville, SC: Part 2 - March 19, 2016
- Fossil Hunting in Summerville, SC: Part 1 - March 3, 2016