Researchers have unearthed a new Jurassic squid-like animal in Wyoming, USA, named Wyoteuthis linsterorum. Dating back roughly 160 million years, the exceptionally rare belemnite features an unusually thick, barrel-shaped skeleton that scientists describe as the chunkiest ever discovered, offering fresh insight into ancient marine predator ecology.
Unearthing the Chunkiest Belemnite in Wyoming’s Sundance Formation
An international team of researchers has formally described a peculiar new species of ancient cephalopod from two exceptionally rare fossils discovered in Wyoming, USA. The newly named species, Wyoteuthis linsterorum, belongs to the belemnites, an extinct group of marine animals closely related to modern squids and octopuses. While millions of standard belemnite fossils fill Wyoming’s ancient inland sea deposits, this specimen breaks every rule of the fossil record.
Most belemnites recovered from the Sundance Formation measure about 5 to 10 centimetres in length and just 1 to 2 centimetres wide. In local field terminology, palaeontologist Jessica Lippincott notes that these common bullet-shaped rostra are informally called squid butts
. By contrast, Wyoteuthis linsterorum possessed an unusually broad, barrel-shaped rostrum reaching 10 centimetres long and up to 6 centimetres wide. Researchers estimate that the living animal, including its arms, may have spanned around 60 centimetres.
Thirty Years in Museum Drawers and Fossil Fields
The journey from rock face to published species description spanned nearly three decades. In the late 1990s, Dr Burkhard Pohl, founder of the Wyoming Dinosaur Center, unearthed the first oversized specimen. That fossil remained unstudied in a collection drawer for years until a second specimen was found by fossil collector Cliff Linster near Ten Sleep, Wyoming, and donated to the museum in 2019. Together, the two fossils provided the necessary data to formally describe the animal in the journal Papers in Palaeontology.
“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.”
Jessica Lippincott, Wyoming palaeontologist and co-author, via Discoverwildlife
The study was initiated by Wyoming palaeontologist Bill Wahl, who remarked that the specimen stuck out like a sore thumb
. To peer inside the fossils without causing destruction, the team used computed tomography (CT) scanning, uncovering internal features that shifted our understanding of belemnite evolution.
Reviving a Long-Lost Ancient Lineage
Anatomical analysis revealed that Wyoteuthis belongs to the family Megateuthididae, a group that typically flourished during the Early to Middle Jurassic and was presumed to have vanished globally prior to the Late Jurassic (Times of India). Finding a member of this lineage preserved in the Upper Redwater Shale of the Sundance Formation demonstrates that a rare surviving branch persisted in North America long after its primary extinction window (Times of India).
Ippolitov noted that after more than two centuries of formal research into belemnites, discovering such an radical departure from established forms is exceptionally rare. The research team points to ecological competition as a driving factor behind its unusual frame.
“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.”
Alexey Ippolitov, Victoria University of Wellington, via Discoverwildlife
Honouring a Passionate Fossil Collector
The genus name Wyoteuthis translates directly to a squid from Wyoming, while the species designation honors Cliff Linster and his family for discovering and donating the crucial holotype (Times of India).
British palaeontologist Dr Dean Lomax, an Honorary Research Fellow at The University of Manchester, had known Linster and his wife Sandy since visiting their northern Montana property in 2009 to excavate dinosaur bonebeds. Reflecting on the publication, Lomax called the timing bittersweet.
“I’m honoured 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 immortalise him and his family name in the history of palaeontology. 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 specialisation.”
Dr Dean Lomax, Honorary Research Fellow at The University of Manchester, via Discoverwildlife
What Next for Wyoming’s Sundance Formation Discoveries
Both official specimens of Wyoteuthis linsterorum remain housed and on public display at the Wyoming Dinosaur Center in Thermopolis. Whether additional specimens of this barrel-shaped predator are locked away in private collections or await discovery in the Redwater Shale remains an open question for regional invertebrate researchers.
The study highlights how amateur rockhounds and dedicated fossil collectors continue to fill vital gaps left by traditional field expeditions (Times of India). As palaeontologists continue applying non-destructive CT imaging to historical museum drawers, researchers will determine if other misunderstood marine fossils warrant reclassification as long-surviving relict lineages.
