Belemnites rank among the most abundant fossils found anywhere in the world. They are recognised by their bullet-shaped remains, known as a rostrum or guard, a dense mineralised structure that anchored the soft tissues of the living animal and is the part most often preserved. Millions of these bullet-shaped fossils have been recovered from Wyoming’s Sundance Formation, the sedimentary record of an ancient inland sea that once covered much of the western United States during the Jurassic period. Local collectors know them so well that, according to Wyoming palaeontologist and study co-author Jessica Lippincott, they are affectionately nicknamed squid butts. Most Wyoming belemnites measure around five to ten centimetres in length and only one to two centimetres across, producing the slender, dart-like profile familiar to fossil hunters everywhere.

The newly discovered species breaks that mould entirely. Its rostrum is around ten centimetres long but reaches up to six centimetres in width, giving it a broad, barrel-like silhouette unlike anything previously recorded in the group. Based on the dimensions of the preserved skeleton, researchers estimate that the living animal would have reached approximately sixty centimetres in total length, including its arms. That makes it not merely a large example of a familiar form, but a genuinely different body plan within a lineage whose fossil record is otherwise remarkably consistent. The discovery is described in the international journal Papers in Palaeontology by an international team of researchers from the United States, the United Kingdom and New Zealand, including Dr Dean Lomax, an Honorary Research Fellow at The University of Manchester.

The scientific journey behind the specimen began almost three decades ago. The first fossil was unearthed in the late 1990s by Dr Burkhard Pohl, founder of the Wyoming Dinosaur Center, who spotted a belemnite far larger than any he had encountered before. Despite its striking appearance, the fossil sat unstudied in a museum collection drawer for many years. The breakthrough came when a second specimen was discovered near Ten Sleep, Wyoming, by fossil collector Cliff Linster, who donated it to the Wyoming Dinosaur Center in 2019. Together, the two fossils provided the comparative evidence needed to confirm that the animals represented something genuinely new rather than simply unusually robust individuals of a known species, and to formally describe and name it.

The investigation was instigated by Wyoming palaeontologist and co-author Bill Wahl, who has spent much of his career searching for fossils across the state and recalled that this particular belemnite stuck out like a sore thumb. Recognising the significance of the specimens, he assembled an international team to study them, including belemnite expert Alexey Ippolitov, now based at Victoria University of Wellington in New Zealand. The team applied computed tomography, or CT scanning, to examine the fossils in fine detail without any risk of damaging them. The scans revealed internal anatomical features that proved decisive: they confirmed the animal belonged to an ancient family of belemnites previously thought to have disappeared millions of years earlier, making Wyoteuthis linsterorum a relict lineage that survived unnoticed into the Late Jurassic of North America.

For specialists who have spent their careers on this group, the find was astonishing. Ippolitov said he was deeply surprised to discover a fossil from such a well-studied group that differed so radically from anything previously known. After more than 200 years of palaeontological research on belemnites, he noted, discoveries of this magnitude are exceptionally rare. The finding underscores how much remains hidden even within heavily sampled rock units and familiar fossil groups, and it demonstrates the continuing value of museum collections, where unstudied specimens can wait decades for the right expertise and comparative material to unlock their significance.

Why this belemnite grew so thick, and why it is so rare, remain open questions, but the researchers offer a provocative ecological hypothesis. According to Ippolitov, a possible explanation is that the animal’s relatively large size gave it an advantage when hunting co-occurring smaller belemnites of the genus Pachyteuthis, the abundant slender forms that dominate Wyoming’s Jurassic deposits. 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. If that interpretation is correct, Wyoteuthis linsterorum may have occupied a predatory niche within the Sundance sea, using its bulk and power to prey upon the very belemnites that swarm in the fossil record around it.

Dr Lomax, who is also an 1851 Research Fellow at the University of Bristol, has a personal connection to the story. He dug up dinosaurs alongside Cliff Linster and his wife Sandy when he was a teenager, and reflected on the honour of naming the fossil after his old friend. He recalled meeting Cliff and Sandy in 2009, when he spent a week excavating a dinosaur bonebed on their property in northern Montana, listening to Cliff share his passion for fossils, including this very belemnite. Lomax described the publication as bittersweet, since Cliff did not live to see it, but noted that the naming immortalises him and his family in the history of palaeontology. He suggested that the find’s incredible rarity might be due to ecological adaptations to the environment at the time, and that perhaps its rarity is a result of narrow specialisation, an animal so tightly tuned to a particular way of life that it left only the faintest trace.

The naming itself carries the story forward. Wyoteuthis translates as a squid from Wyoming, while the species name linsterorum honours Cliff Linster and his family. Cliff discovered one of only two known specimens of the new species and donated it for scientific study, and he knew researchers were working on his find and was excited to see it formally described before his death in June this year. The Linster family are no strangers to remarkable fossils, perhaps most famously the dinosaur Bambiraptor. Jessica Lippincott, who has spent years collecting the common Pachyteuthis belemnites of Wyoming, said this one is unlike anything she has ever seen, adding that people who rockhound or collect invertebrate fossils can also contribute to science. Both specimens are now on display at the Wyoming Dinosaur Center in Thermopolis, Wyoming, and Lomax, author of the recently published book The Secret Lives of Dinosaurs, which highlights Wyoming fossils, hopes the discovery will inspire a new generation of collectors to look more closely at the stones beneath their feet.

Subject of Research: A new species of unusually thick Late Jurassic belemnite from the Sundance Formation of Wyoming, USA

Article Title: “Peculiar” new species of Jurassic squid found in Wyoming

Article References: “Peculiar” new species of Jurassic squid found in Wyoming. (n.d.). Original publication

Image Credits: AI Generated

DOI: Not provided

Keywords: belemnite, Jurassic, Wyoming, cephalopod, paleontology, Sundance Formation, fossil, CT scanning, new species, Wyoteuthis linsterorum, inland sea, museum collections

The bonebed, discovered at a site known as Nobby Knob in Dubois, Wyoming, fascinates paleontologists due to its context. Unlike many fossil sites where the arrangement of bones can indicate transportation or disturbance after death, the evidence from Nobby Knob suggests a more tranquil scenario. This site has yielded a high concentration of fossilized remains from a particular species, Buettnererpeton bakeri, indicating that these amphibians might have come together for breeding or as a result of environmental constraints, such as drought, which restricted their movements.

The preservation quality of the bones presents another compelling aspect of the study. The fine-grained ancient soils and the carefully layered sediments imply that the burial process was gentle. Unlike typical bonebeds where strong currents may have displaced remains, the fossils at Nobby Knob remained undisturbed, allowing for the preservation of delicate skeletal structures. This unique factor provides a rare opportunity for scientists to analyze the anatomical details of Buettnererpeton bakeri, deepening our understanding of its morphology and biology.

The findings from this site are extraordinarily significant as they represent a substantial fraction of all known Buettnererpeton fossils, effectively doubling the previously documented individuals of this species. By accumulating a diverse assortment of individual characteristics, researchers can conduct more comprehensive analyses to determine how these amphibians adapted to their environments. This also opens new avenues for research into the ecological roles of metoposaurids during the Late Triassic period.

While the significance of this discovery is evident, one crucial question remains: Was such a mass die-off a common phenomenon among metoposaurids? The context of the Nobby Knob field site is rare, as few other similar sites have undergone rigorous examination. Many other known bonebeds of temnospondyls represent accumulations of remains transported over considerable distances, due to environmental factors or incidents. The uniqueness of Nobby Knob allows researchers to view the fossil assemblage as a snapshot of a single population, thereby facilitating more in-depth studies into the behaviors and challenges these ancient amphibians faced.

Further investigations into sediment variations and the biotic interactions within this ancient habitat will enhance our understanding of the Late Triassic ecosystems. As Kufner aptly summarizes, this assemblage sheds light on the ecological dynamics that may have defined the life cycles of metoposaurids at that time. Although the current findings contribute significantly to the field of paleontology, researchers argue that more extensive mapping and meticulous data collection during excavation processes are vital for unlocking further mysteries surrounding ancient terrestrial ecosystems.

In the context of broader paleontological research, this study serves as a reminder of the value of collaborative and well-organized fieldwork. The importance of systematic examination cannot be overstated, especially in a time where fossils provide crucial insights into the evolution of present-day species. As we peer into the depths of ancient history through fossils, it’s clear that each discovery is not merely an end in itself but rather an invitation for further exploration into life’s history on Earth.

The specific methods employed by Kufner and his colleagues included meticulous excavation and analysis of the fossilized remains, alongside thorough examinations of the surrounding geological context. These approaches are essential in unraveling the complex interactions that occurred in prehistoric settings. The outstanding preservation quality of the fossils at Nobby Knob allows scientists to advance their inquiry into the biology of ancient amphibians, making it imperative to establish more sites that might yield similar findings in the future.

The research ultimately underscores the complexity of extinction events and mass mortality, reminding us that the factors driving these phenomena are multifaceted. As this work highlights, environmental stresses such as drought and other ecological pressures likely contributed to the conditions that led to the entrapment of these amphibians in the sediment. Thus, the Nobby Knob site is more than just a resting place for ancient creatures; it encapsulates the dynamics of a historical moment that could inform our understanding of contemporary biodiversity and ecosystem resilience.

Furthermore, the implications of this research extend beyond just the context of metoposaurids. By understanding how ancient amphibians responded to their environment, scientists can derive parallels to how modern species might cope with the rapidly changing climate today. Future research initiatives are essential to map more fossil assemblages and draw comparisons across different sites and conditions, ultimately enriching our collective knowledge of life across geological timescales.

In conclusion, the metoposaurid bonebed study at Nobby Knob has opened new avenues of inquiry into the lives of prehistoric amphibians, showcasing the meticulous nature of paleontological research. As scientists continue to decipher the nuances of the fossil record, the answers emerging from such investigations can educate not just the academic community, but also the public on the intricacies of Earth’s biological heritage. The legacy of these ancient creatures needs to be cherished and understood as we navigate the ongoing challenges facing biodiversity in our current era.

As we reflect on the past through the lens of fossil discoveries, it becomes increasingly clear that the lessons learned may hold vital keys to understanding the future of our planet’s ecosystems.

Subject of Research: Animals
Article Title: A new metoposaurid (Temnospondyli) bonebed from the lower Popo Agie Formation (Carnian, Triassic) and an assessment of skeletal sorting
News Publication Date: 2-Apr-2025
Web References: Link to the article
References: Kufner AM, Deckman ME, Miller HR, So C, Price BR, Lovelace DM (2025) A new metoposaurid (Temnospondyli) bonebed from the lower Popo Agie Formation (Carnian, Triassic) and an assessment of skeletal sorting. PLoS ONE 20(4): e0317325.
Image Credits: Credit: Dave Lovelace, CC-BY 4.0

Keywords: Metoposaurid, Buettnererpeton, Triassic, PLOS One, bonebed, paleoecology, ancient ecosystems, amphibian extinction.