Two extraordinarily rare fossils found in Wyoming have revealed a strange new species of squid relative that lived approximately 160 million years ago, during the Jurassic Period.
Named Wyoteuthis linsterorum, the prehistoric creature belonged to an extinct group of marine animals known as belemnites, which were related to modern squid and octopuses. What makes this species particularly remarkable is its unusually thick, barrel-shaped internal skeleton, earning it the distinction of being the “chunkiest” or “fattest” belemnite ever identified.
An international research team from the United States, United Kingdom, and New Zealand, including Dr. Dean Lomax, an Honorary Research Fellow at The University of Manchester, detailed the discovery in the scientific journal Papers in Palaeontology.
An Unusually Thick Jurassic Squid Relative
Belemnites are among the most frequently discovered fossils in the world. They are best known for their distinctive, bullet-shaped internal skeletal structures, called rostra or guards, which are often the only parts of the animals that survive in the fossil record.
Wyoming’s Sundance Formation, which preserves evidence of an ancient inland sea that once stretched across much of the western United States, has yielded millions of these fossils. According to Wyoming paleontologist and study coauthor Jessica Lippincott, they are commonly nicknamed “squid butts” in the region.
Most belemnite fossils from Wyoming have a narrow, bullet-shaped appearance, typically measuring between 5 and 10 centimeters in length and just 1 to 2 centimeters across. The newly identified species is dramatically different. Its rostrum measures approximately 10 centimeters long but reaches an extraordinary 6 centimeters in width, making it the thickest known example of its kind.
Scientists estimate that the living animal, including its arms, could have reached a total length of approximately 60 centimeters, or about two feet.
Rare Fossils Reveal a Surprising Evolutionary Secret
Wyoming paleontologist Bill Wahl, who has devoted much of his career to searching for fossils across the state, recognized that the unusual specimen deserved closer examination. He said the belemnite “stuck out like a sore thumb” compared with the countless others found in the region.
Wahl assembled an international team to investigate the fossils, bringing in specialists including belemnite expert Alexey Ippolitov, a PhD student now based at Victoria University of Wellington in New Zealand.
The researchers used computed tomography (CT) scanning to investigate the fossils’ internal structures without damaging the specimens. These detailed scans revealed an unexpected connection to an ancient belemnite family that scientists had believed disappeared millions of years before this animal lived.
Ippolitov said he was “deeply surprised” to encounter such an unusual specimen from a group that has already been studied extensively. Belemnites have been the subject of paleontological research for more than 200 years, making the identification of such a radically different species especially remarkable.
The creature’s unusual proportions may also offer clues about how it lived and hunted.
Ippolitov explains: “A possible explanation is that their relatively large size gave them an advantage when hunting co-occurring smaller belemnites of the genus Pachyteuthis. Modern squid, after all, are hardly picky when it comes to prey: they readily hunt not only other species of cephalopods, but sometimes even their own kind.”
A Fossil Discovery Nearly 30 Years in the Making
Although the species has only now been formally described, its discovery began almost three decades ago.
The first known specimen was found in the late 1990s by Dr. Burkhard Pohl, founder of the Wyoming Dinosaur Center. While examining fossils, Pohl noticed a belemnite that was considerably larger than any he had previously encountered.
Despite its unusual appearance, the specimen remained unstudied in a museum collection drawer for many years.
A breakthrough came when fossil collector Cliff Linster discovered a second specimen near Ten Sleep, Wyoming. He donated the fossil to the Wyoming Dinosaur Center in 2019, providing researchers with another example of the mysterious animal.
With two specimens available for comparison, scientists finally had enough evidence to recognize and formally describe an entirely new species.
The genus name Wyoteuthis means “a squid from Wyoming,” while the species name linsterorum recognizes Cliff Linster and his family for their contributions. Linster discovered one of the only two known examples and ensured it was available for scientific research.
Lippincott emphasized how extraordinary the discovery was, even for researchers familiar with Wyoming’s abundant belemnite fossils.
“After spending years fossil hunting in Wyoming and collecting countless fossils of the common Pachyteuthis belemnites here in Wyoming, this one is unlike anything I have ever seen! It goes to show that we are still finding new species of fossils all the time, and people who rockhound or collect invertebrate fossils can also contribute to science.”
Honoring a Fossil Hunter’s Remarkable Legacy
Sadly, Cliff Linster passed away in June before the research was published. He had been aware that scientists were investigating his discovery and was enthusiastic about seeing the unusual fossil receive formal scientific recognition.
The Linster family already had an impressive history of fossil discoveries, including their association with the famous dinosaur Bambiraptor.
For British paleontologist Dr. Dean Lomax, the discovery also carries considerable personal meaning. Lomax, an Honorary Research Fellow at The University of Manchester and an 1851 Research Fellow at the University of Bristol, first worked alongside Cliff and his wife, Sandy, while excavating dinosaur fossils as a teenager.
He said: “I met Cliff and Sandy in 2009, when I spent a week digging up a dinosaur bonebed on their property in northern Montana. I have fond memories of that dig, listening to Cliff share his passion for fossils, including this belemnite. I’m honored to help name this fossil after Cliff. It’s bittersweet that he didn’t get to see it published, but it’s wonderful that we can immortalize him and his family name in the history of paleontology. The find is incredibly rare, which might be due to some ecological adaptations to the environment at the time. Perhaps its rarity is a result of narrow specialization.”
Lomax has extensive experience studying Wyoming’s prehistoric animals, including collecting fossils and excavating plesiosaurs and ichthyosaurs from the Sundance Formation. He is also the author of the recently published book “The Secret Lives of Dinosaurs,” which features fossils from Wyoming.
The discovery highlights how even well-studied fossil groups can still hold major surprises, particularly when unusual specimens are preserved and made available for scientific investigation.
Both known fossils of Wyoteuthis linsterorum are now on display at the Wyoming Dinosaur Center in Thermopolis, Wyoming, where visitors can see the extraordinary remains of one of the Jurassic seas’ most unusual squid relatives.
The findings are published in the international journal Papers in Palaeontology.
