February, 2024 | Everything Dinosaur Blog

19 02, 2024

New Study Demonstrates Tridentinosaurus Fossil is a Fake

By Mike|2024-02-19T12:35:47+00:00February 19th, 2024|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Main Page, Palaeontological articles, Photos/Pictures of Fossils|0 Comments

A fossil once thought to represent an Early Permian reptile with soft tissue preservation has been proven to be a fake. The fossilised remains of a lizard-like reptile named Tridentinosaurus antiquus were found in the 1930s. It was thought to be an extremely rare fossil with carbonised skin impressions surrounding the articulated fossil bones. However, a detailed analysis of the specimen has revealed that these “soft tissues” were painted on.

Images of the Tridentinosaurus antiquus fossil specimen. — Tridentinosaurus antiquus fossil specimen (A) showing sampling locations with (B) surface map of the fossil. The specimen photographed under UV light (C). Analysis revealed that the purported fossilised soft tissues of T. antiquus were forged. Picture credit: Rossi et al.

Tridentinosaurus antiquus Specimen is a Forgery

Discovered in the Italian Alps near the “Stramaiolo” (Redebus) locality in the Pinè Valley, the fossil was thought to represent one of the oldest, nearly complete and articulated reptiles known to science. Writing in the journal “Palaeontology”, the research team used a variety of techniques to analyse the surface structure of the twenty-centimetre-long fossil.

The results demonstrated that the purported fossilised soft tissues of Tridentinosaurus antiquus are not original. The fossil is a forgery. The paint applied within the prepared area around the poorly preserved bones and osteoderms, produced the shape of a slender lizard-like animal making the specimen look authentic.

Carbonised plant remains are known from the same locality. The forged body outline and soft tissues misled scientists who thought that the soft tissue had been carbonised just like plant fossils from this region. Under ultraviolet light the plant fossils did not fluoresce, however, the reptile fossil outline became fluorescent. Normally, carbonised fossil material does not fluoresce when exposed to UV light. However, artificial pigments, vanishes and glues are likely to become fluorescent.

The Validity of the Taxon is Doubted

Tridentinosaurus antiquus represents one of the oldest fossil reptiles known to science. The taphonomy and the appearance of this fossil had puzzled palaeontologists for decades. It was thought to represent a primitive diapsid reptile, a basal member of the Archosauromorpha that gave rise to the dinosaurs, crocodiles and birds.

The researchers were able to confirm that many of the features of this specimen had been forged. This discovery raises questions about the validity of this enigmatic taxon.

Despite the manipulation of the specimen, it may still have scientific value. The poorly preserved long bones of the hindlimbs seem to be genuine and resemble the quality of preservation of exposed bones of Late Triassic pterosauromorphs such as Scleromochlus. Perhaps, this fossil is an example of the lineage of basal archosaurs that gave rise to the flying reptiles (Pterosauria).

Close-up views of the Tridentinosaurus antiquus fossil specimen. — Close-up view of the shoulder area (D) and an enlargement of the pelvic girdle (E). Although much of the fossil has been altered some bones seem to be genuine and resemble the quality of preservation of exposed bones of Late Triassic pterosauromorphs such as Scleromochlus. Scale bar in (D) equals 5 mm. The scale bar (E) equals 3 mm. Picture credit: Rossi et al.

Why Fake a Fossil?

Fossils are sometimes manipulated to make them more valuable to collectors. If the fossil can be seen to be more complete or rare it can greatly enhance their monetary value.

Everything Dinosaur acknowledges the assistance of a media release from the Museum of Nature South Tyrol (Naturmuseum Südtirol) in the compilation of this article.

The scientific paper: “Forged soft tissues revealed in the oldest fossil reptile from the early Permian of the Alps” by Valentina Rossi, Massimo Bernardi, Mariagabriella Fornasiero, Fabrizio Nestola, Richard Unitt, Stefano Castelli, Evelyn Kustatscher published in Palaeontology.

Visit the Everything Dinosaur website (there are no fakes here): Everything Dinosaur.

18 02, 2024

Frogspawn Discovered in the Office Pond

By Mike|2024-02-18T21:22:20+00:00February 18th, 2024|Animal News Stories, Educational Activities, Main Page, Photos|0 Comments

We have frogspawn in the office pond. Today, a clump of frogspawn was observed in a shallow area of the office pond. Frogs had been spotted in the pond a few days ago, it seems that the spawning season has started. This is the earliest date in the year that we have recorded frogspawn. Last year (2023), the first frogspawn was recorded on the 28th of February. This was the first time that the frogs have spawned in February. This year, the frogs have begun spawning even earlier.

Picture credit: Everything Dinosaur

Common Frogs (Rana temporaria)

The spawn was produced by Common frogs (Rana temporaria). Observations by team members suggest that there were four frogs in the pond. The pond has been created to attract wildlife and frogs have laid their eggs in the pond each spring since 2008. For many years the frogs spawned around the third week of March. However, there is a distinct trend for recording spawning much earlier in the year.

Could this be a consequence of global warming and climate change?

It has certainly been very mild over the last week or two. Temperatures of 13-14 degrees Celsius have been recorded in the northwest of England. The average temperature for February in the Manchester area of England would normally be expected to be around 4-7 degrees Celsius.

A close-up view of the frogspawn (18th February, 2024). — *A close-up view of the frogspawn laid early in the morning of 18th February.* *Picture credit: Everything Dinosaur.*

Picture credit: Everything Dinosaur

Frogspawn Laid in a Shallow Part of the Pond

The frogs have laid their eggs in a shallow part of the pond. Eggs are not normally laid in this part of the office pond. Folklore suggests that if frogs lay in the shallows, then the next few weeks will be mild but wet. We will continue to observe the pond to see if more frogs arrive and more spawn is produced.

The Everything Dinosaur website: Everything Dinosaur.

17 02, 2024

The Popular Mojo Fun Woolly Rhinoceros Model

By Mike|2024-02-19T05:52:13+00:00February 17th, 2024|Adobe CS5, Dinosaur Fans, Everything Dinosaur News and Updates, Everything Dinosaur Products, Main Page, Photos of Everything Dinosaur Products|0 Comments

Everything Dinosaur has received some new images of Mojo Fun prehistoric animal models. One of our favourites highlights the recently introduced Mojo Fun Woolly Rhinoceros. This replica of Coelodonta antiquitatis was introduced in 2023. The model has proved to be extremely popular with prehistoric animal model collectors.

To view the extensive range of Mojo Fun prehistoric animal figures available from Everything Dinosaur: Mojo Fun Prehistoric and Extinct Figures.

The Mojo Fun Woolly Rhinoceros Model

This Woolly Rhino model measures approximately 18 cm in length. Everything Dinosaur team members estimate its head height is around 7 cm. It is a stunning figure of a prehistoric mammal.

Mojo Fun Woolly Rhino model. — *The new for 2023 Mojo Fun Woolly Rhino model is in stock. Picture credit: Everything Dinosaur.*

Picture credit: Everything Dinosaur

A spokesperson from Everything Dinosaur praised Mojo Fun for their excellent Woolly Rhino image and added:

“The Woolly Rhino is synonymous with the Ice Age. However, these magnificent animals were geographically widespread during the Pleistocene Epoch and thrived in grassland habitats.”

Visit the award-winning Everything Dinosaur website: Everything Dinosaur.

16 02, 2024

Lungfish and the Remarkable History of Fossil Holes

By Mike|2024-02-16T12:32:09+00:00February 16th, 2024|Adobe CS5, Animal News Stories, Main Page|0 Comments

Yesterday, Everything Dinosaur team members posted up an article that provided information on the evolutionary history of burrowing vertebrates. The first vertebrates to dig burrows were probably lungfish. These animals were similar to extant lungfish, animals such as Neoceratodus forsteri, the Australian lungfish. This taxon is also referred to as the Queensland lungfish.

Ironically, it is thought that this species of lungfish does not enter a dormant state (aestivation), by producing a mucous cocoon and burying itself in mud. Neoceratodus forsteri inhabits slow-moving rivers and reservoirs, primarily in south-eastern Queensland. In contrast, the African genus Protopterus does dig burrows. Protopterus is distantly related to the Australian lungfish. During the dry season when lakes tend to dry up, this fish excavates a burrow and buries itself in the mud. It enters a state of dormancy (aestivation), enabling it to survive whilst it waits for the water to return. During aestivation Protopterus is able to reduce its metabolism to 1/60th of its active state.

The Australian lungfish (Neoceratodus forsteri). — *A stuffed specimen of an Australian lungfish (Neoceratodus forsteri) on display at the London Natural History Museum. Picture credit: Everything Dinosaur.*

Picture credit: Everything Dinosaur

A team of researchers, including scientists from the Museum für Naturkunde Berlin examined the origins and early evolution of vertebrate burrowing behaviour. Their paper was published in Earth-Science Reviews.

To read Everything Dinosaur’s article about this new research: Digging into the History of Burrowing Vertebrates.

The Scientific Paper

The scientific paper comprises a short overview of convergent morphological and behavioural adaptations seen in modern fossorial taxa. The researchers also document the diversity of extant vertebrate burrows. In addition, the team reviews the fossil record of inferred vertebrate burrows and fossorial vertebrates from the Devonian to the Triassic. Results highlight a probable Devonian earliest occurrence of fossoriality in continental vertebrates (Dipnoi – lungfishes).

The earliest lungfish taxa were mostly marine animals. However, after the Carboniferous, lung fish fossils are confined to deposits laid down in freshwater environments.

The Australian lungfish specimen at the London Natural History Museum is displayed next to a model of a Protopterus burrow. This can confuse visitors, it was stated earlier in this article that not all lungfish exhibit this burrowing behaviour.

The award-winning Everything Dinosaur website: Everything Dinosaur.

15 02, 2024

Digging into the History of Burrowing Vertebrates

By Mike|2024-02-16T08:53:17+00:00February 15th, 2024|Dinosaur Fans, Main Page, Palaeontological articles|0 Comments

A newly published scientific paper documents the evolutionary history of burrowing vertebrates. Many animals alive today are able to live underground. Burrows are used for a variety of purposes. They are used for shelter, protection and for breeding. Understanding the origin and early evolution of fossorial vertebrates and the architecture and function of the burrows they excavate is an important component of the history of life on Earth. However, little research has been done into this area of vertebrate behaviour. A newly published scientific paper reviews the fossil record of vertebrate burrows and fossorial vertebrates.

Jehol mammals Fossiomanus sinensis and Jueconodon cheni — Two new species of Early Cretaceous mammals were described from fossils found in north-eastern China. Fossiomanus sinensis (upper right) and Jueconodon cheni in their burrows. A newly published scientific paper reviews the fossil record of burrowing vertebrates. Picture credit: Zhao Chuang.

Picture credit: Zhao Chuang

The Evolution of Burrowing Vertebrates

Scientists including Dr Lorenzo Marchetti and colleagues from the Museum für Naturkunde Berlin analysed both body and trace fossils. The fossil material covered a large interval of geological time, from the Devonian to the Triassic. The research revealed an older appearance of several features related to burrowing behaviour and their relationship with global warming and mass extinctions.

During the Devonian-Carboniferous, burrows were probably used primarily for aestivation or temporary shelter and evidence of fossoriality is restricted so far to European and North American localities. During the Permian, fossoriality became geographically widespread and developed in new, distantly related vertebrate lineages. This is evidence of convergent evolution. Adaptations for burrowing and living underground being identified in both synapsids and diapsids.

The research highlights that lungfish (Dipnoi) were probably the first vertebrates to use burrows. Lungfish excavate burrows so that they have a protected environment in which they can spend long periods in a state of dormancy (aestivation). This behaviour probably first evolved in the Devonian.

Burrows Became Bigger and More Complex

The paper, published in “Earth-Science Reviews” outlines a trend for bigger and more complex burrows during the Palaeozoic and into the Mesozoic. Burrows became permanent shelters and breeding locations. The researchers link these developments to climate crises such as the Cisuralian aridification (Early Permian) and the end-Permian extinction event.

After the end-Permian mass extinction, vertebrate fossoriality became more common and widespread. This behaviour became a feature of continental environments and in more distal floodplain areas, probably as a consequence of changing fluvial regimes. In the Triassic, fossoriality is recorded in even more groups, such as the Temnospondyli and the Procolophonidae. In addition, evidence of burrow sharing by unrelated vertebrates appears. This indicates that burrowers were playing an increasing role as ecosystem engineers.

Everything Dinosaur acknowledges the assistance of a media release from the Museum für Naturkunde Berlin in the compilation of this article.

The scientific paper: “Origin and early evolution of vertebrate burrowing behaviour” by Lorenzo Marchetti, Mark J. MacDougall, Michael Buchwitz, Aurore Canoville, Max Herde, Christian F. Kammerer and Jörg Fröbisch published in Earth-Science Reviews.

Visit the Everything Dinosaur website: Everything Dinosaur.

14 02, 2024

The New Wild Safari Prehistoric World Utahraptor Model

By Mike|2024-03-03T06:42:36+00:00February 14th, 2024|Adobe CS5, Dinosaur Fans, Everything Dinosaur News and Updates, Everything Dinosaur Products, Main Page, Photos of Everything Dinosaur Products, Press Releases|0 Comments

The Wild Safari Prehistoric World Utahraptor dinosaur model is now in stock. This extremely colourful and detailed dromaeosaur model is available from Everything Dinosaur. Team members got the opportunity to photograph the figure whilst visiting a trade show in Europe.

Utahraptor dinosaur model (Wild Safari Prehistoric World). — The Wild Safari Prehistoric World Utahraptor model spotted at a trade show. The soon to be available colourful Kentrosaurus figure can be seen to the left of the Utahraptor. Picture credit: Everything Dinosaur.

Picture credit: Everything Dinosaur

To view the range of Wild Safari Prehistoric World figures available from Everything Dinosaur: Safari Limited – Wild Safari Prehistoric World Models.

The Utahraptor Dinosaur Model

This hand-painted Utahraptor replica measures twenty-three centimetres in length. It stands around eleven and a half centimetres tall. It is an extremely colourful dinosaur model. The vivid blue colouration reminds us of a budgerigar. Dromaeosaurids like Utahraptor are, after all, distantly related to modern birds. The Wild Safari Prehistoric World Utahraptor dinosaur model is supplied with an Everything Dinosaur Utahraptor fact sheet.

The Wild Safari Prehistoric World Utahraptor dinosaur model. — *A Wild Safari Prehistoric World Utahraptor dinosaur model.*

A spokesperson from Everything Dinosaur welcomed the arrival of the Utahraptor dinosaur model. Other new figures from Safari Ltd will be available later in the year.

The Wild Safari Prehistoric World Utahraptor dinosaur model unpacked in the Everything Dinosaur warehouse. — *Unpacking the new Wild Safari Prehistoric World Utahraptor dinosaur figure. Picture credit: Everything Dinosaur.*

Picture credit: Everything Dinosaur

To view the extensive range of prehistoric animal figures and dinosaur toys available from Everything Dinosaur’s award-winning website: Visit Everything Dinosaur.

13 02, 2024

Studying Stunning Sea Scorpion Fossils

By Mike|2024-03-03T12:39:31+00:00February 13th, 2024|Adobe CS5, Educational Activities, Main Page, Palaeontological articles, Photos/Pictures of Fossils|0 Comments

Eurypterids (Eurypterida) are often referred to as sea scorpions. Like scorpions these extinct invertebrates are members of the Arthropoda Phylum. They are distantly related to extant scorpions and spiders. It is thought that the first eurypterids evolved during the Ordovician. They thrived in the Silurian and Devonian. Giant forms evolved, animals like Jaekeklopterus, Acutiramus and Pterygotus. However, the number of taxa was severely depleted during the end-Devonian extinction event and although they survived for at least another 100 million years or so, during the Carboniferous and Permian they only made up a very small percentage of the taxa described from fossil deposits.

Two Pterygotus sea scorpion fossils. — Examples of the Pterygotioidea eurypterid lineage. Note the flattened, blade-like telson that probably helped with propulsion or acted like a rudder helping to steer the animal through the water. The fossils represent Pterygotus anglicus. Picture credit: Everything Dinosaur.

Picture credit: Everything Dinosaur

The picture (above) shows two Pterygotus anglicus fossil specimens on display at the London Natural History Museum. These Early Devonian fossils come from Arbroath (Scotland).

The Shape of the Telson

Note the broad, flattened, blade-like final segment of the animal. This is the telson and in the Pterygotioidea lineage (as well as in some other Superfamilies), the telson evolved into an organ to help with propulsion and steering. In other eurypterids, the telson is shaped very differently. For example, in the sea scorpion fossil (below), the telson is long and pointed.

Examining sea scorpion fossils — A fossil of a sea scorpion (eurypterid) on display at the Manchester Museum. Note the pointed end segment (telson). Probably an example of the Silurian eurypterid Eurypterus. Picture credit: Everything Dinosaur.

The Giant Claws (Chelicerae) Seen in Some Sea Scorpion Fossils

The segmented body of eurypterids consisted of the frontal prosoma (head) and the posterior opisthosoma (abdomen). The prosoma contained the mouth and six pairs of appendages which are usually referred to as appendage pairs I to VI using Roman numerals. The segments that make up the opisthosoma are usually numbered using Arabic numerals 1, 2, 3 etc. The opisthosoma comprised twelve segments in total plus the telson.

The first pair of appendages, the only pair located in front of the mouth opening, is called the chelicerae (pronounced kel-iss-ser-ray). This pair of appendages evolved into a myriad of forms in the Chelicerata (pronounced kel-iss-ser-rat-ah), the Subphylum containing the eurypterids, spiders, mites, scorpions and horseshoe crabs. This pair of appendages form the fangs seen in spiders and form the feeding limbs of horseshoe crabs.

An Atlantic horseshoe crab viewed ventrally. — An Atlantic horseshoe crab in ventral view with the six pairs of appendages and the telson labelled. The first pair of appendages (chelicerae) help to push food into the mouth opening. Picture credit: Everything Dinosaur.

Picture credit: Everything Dinosaur

Powerful Pincers Adapted for Grasping Prey

Some of these appendages, such as the chelicerae of giant pterygotids evolved into powerful pincers armed with strong claws analogous to those seen in crabs and lobsters. These chelicerae seem to be adapted for grasping and subduing prey. This suggests that many eurypterids were predatory.

A sea scorpion claw — *A stunning fossil of a sea scorpion (eurypterid) claw housed at the National Museum Cardiff (Wales) photographed in 2019 when team members at Everything Dinosaur visited.* *The image shows a single chelicera ramus. Picture credit: Everything Dinosaur.*

Note

A single appendage is referred to as a chelicera (pronounced kel-iss-ser-rah). Whereas a pair or more are referred to as chelicerae (kel-iss-ser-ray).

A spokesperson from Everything Dinosaur commented that these arthropods were remarkable animals.

“Some 250 different taxa have been described and some of these sea scorpions show adaptations that indicate they may have been partially terrestrial. Venturing out onto land is supported by trace fossils potentially preserving tracks of eurypterids walking across mud close to bodies of water.”

Visit the Everything Dinosaur website: Everything Dinosaur’s Website.

12 02, 2024

The CollectA Horseshoe Crab Model is Reviewed

By Mike|2024-02-24T17:06:48+00:00February 12th, 2024|Adobe CS5, Animal News Stories, Educational Activities, Everything Dinosaur Products, Main Page, Photos of Everything Dinosaur Products|0 Comments

In 2020, CollectA introduced a Horseshoe crab model. These animals are members of the Limulidae family. This model of an ancient invertebrate is extremely detailed. The Horseshoe crab lineage has a fossil record that dates back to the Ordovician. Team members were asked to take some photographs of the figure for a palaeontology related project.

CollectA Horseshoe crab model in lateral view. — *CollectA Horseshoe crab in lateral view. Picture credit: Everything Dinosaur.*

Picture credit: Everything Dinosaur

The CollectA Horseshoe Crab Model

The model is very detailed, and the paint scheme makes this replica look extremely realistic. However, it is on the underside where the care and dedication of the design team really shows.

*The CollectA Horseshoe crab model in ventral view (view of the underside). Picture credit: Everything Dinosaur.*

Picture credit: Everything Dinosaur

To view the not-to-scale CollectA range of models available from Everything Dinosaur: CollectA Prehistoric Life Models.

The small chelicerae (modified claws) are bent towards the mouth. These appendages pass food into the mouth. The walking legs show the bifurcated end segments, and the rear “pusher” leg is clearly visible. The design team have included a vent at the base of the long, pointed telson.

Atlantic Horseshoe crab in ventral view. — *An Atlantic Horseshoe crab in ventral view (view of the underside). Picture credit: Everything Dinosaur.*

Picture credit: Everything Dinosaur

The picture (above) shows an Atlantic Horseshoe crab (Limulus polyphemus) in ventral view. It is on display at the London Natural History Museum.

CollectA Horseshoe Crab model. — *CollectA Age of Dinosaurs Popular Size Horseshoe crab figure. The model measures 15 centimetres in length and the width of the carapace is 7.7 cm approximately.*

In horseshoe crabs, the head and thorax are fused. This structure is called the prosoma. It is also sometimes referred to as the cephalothorax. The cephalothorax is covered in a hard, protective carapace.

Visit the Everything Dinosaur website: Take a Look at the Everything Dinosaur Website.

11 02, 2024

Mojo Fun Pays Tribute to Dinosaurs in the Movies

By Mike|2024-09-18T13:40:26+01:00February 11th, 2024|Adobe CS5, Dinosaur Fans, Everything Dinosaur News and Updates, Everything Dinosaur Products, Main Page|0 Comments

Our thanks to Mojo Fun for sending Everything Dinosaur some new images of the Mojo Fun prehistoric life dinosaur models. The images we received includes a clever illustration of a Mojo Fun Tyrannosaurus rex model.

We think this T. rex dinosaur model was introduced into the Mojo Fun prehistoric and extinct range in 2020. It has certainly proved to be popular with dinosaur fans and model collectors. The manufacturer has paid tribute to dinosaurs in films by mimicking a famous scene from the “Jurassic Park/Jurassic World” franchise.

Mojo Fun Tyrannosaurus rex

The Mojo Fun T. rex figure is escaping from captivity. The image parodies scenes from the famous Universal Studio’s film franchise.

To view the Mojo Fun prehistoric life model range available from Everything Dinosaur: Mojo Fun Prehistoric Life Figures.

The Mojo Fun Tyrannosaurus rex Deluxe figure measures around 30 cm in length. Team members at Everything Dinosaur estimate its head height to be approximately 11 cm.

A spokesperson from Everything Dinosaur commented:

“Every dinosaur fan will get the connection between the Mojo Fun T. rex image and the movies. There are rumours circulating that a new film in the “Jurassic Park/Jurassic World” franchise will be released in 2025. Mojo Fun’s timing of the release of this new image is apposite.”

Visit the award-winning Everything Dinosaur website: Everything Dinosaur.

10 02, 2024

Getting to Grips with the Enigmatic Caenagnathidae

By Mike|2024-02-07T10:13:48+00:00February 10th, 2024|Dinosaur and Prehistoric Animal Drawings, Dinosaur Fans, Main Page, Palaeontological articles, Photos of Everything Dinosaur Products, Photos/Pictures of Fossils|0 Comments

With the publication of the scientific paper announcing the discovery of Eoneophron infernalis, we at Everything Dinosaur thought we would take a closer look at the Caenagnathidae. The Caenagnathidae family (pronounced seen-nag-nay-thid-ay), are part of the Oviraptorosauria clade of maniraptoran theropod dinosaurs. They are closely related to the oviraptorids (Oviraptoridae family).

Anzu wyliei scale drawing. — A scale drawing of a dinosaur (Anzu wyliei). This dinosaur is a member of the Caenagnathidae family, and its fossils come from the Hell Creek Formation (Maastrichtian faunal stage of the Late Cretaceous). Picture credit: Everything Dinosaur.

Picture credit: Everything Dinosaur

To read the recent article about Eoneophron infernalis: University Student Discovers New Dinosaur Species.

Defining the Maniraptora and the Oviraptorosauria

The Maniraptora clade consists of coelurosaurian dinosaurs and is defined as including the birds and the non-avian dinosaurs more closely related to them than to Ornithomimus velox. As well as containing the Oviraptorosauria, this clade also includes several other groups such as the dromaeosaurids, the Troodontidae family and the therizinosaurs.

The Oviraptorosauria clade* is comprised of the Caudipteridae family and two closely related dinosaur families the Caenagnathidae and the Oviraptoridae that together are classified as the Caenagnathoidea. The Oviraptorosauria are united by having very bird-like skeletons, with highly pneumatised bones. In addition, the rostrum is very short, and these dinosaurs have beaks. The beak is often, but not always edentulous (no teeth). These dinosaurs were all probably feathered.

A model of an Oviraptor. — *An Oviraptor dinosaur model (CollectA Age of Dinosaurs).*

The image (above) depicts an Oviraptor model from the CollectA Age of Dinosaurs range.

To view this range of prehistoric animal figures: CollectA Age of Dinosaurs/Prehistoric Life Models.

The Caenagnathidae Family and Eoneophron infernalis

The family Caenagnathidae, together with its closely related sister family the Oviraptoridae, comprises the superfamily Caenagnathoidea. Virtually all known members of this superfamily are confined to the Late Cretaceous. Taxonomically the Caenagnathidae is defined as Chirostenotes pergracilis and all other theropods more closely related to it than they are to Oviraptor philoceratops.

Most of these dinosaurs tend to be quite small. As a result, they are probably underrepresented in the fossil record. For example, Anzu wyliei was thought until recently to be the only caenagnathid from the Hell Creek Formation. However, there are probably at least three caenagnathids present in Hell Creek strata, including the recently named Eoneophron infernalis.

Eoneophron infernalis limb bones — *The femur (left) and right tibia (right) of Eoneophron. Picture credit: Kyle Atkins-Weldman.*

Caenagnathids Not Closely Related to Ostriches

The Caenagnathidae family was originally erected by Raymond Martin Sternberg (1940), the son of the pioneering palaeontologist Charles Mortram Sternberg. Raymond Martin Sternberg thought that these dinosaurs were flightless birds. He erected the Caenagnathidae family which translates as “recent jaws”. It was mistakenly thought that these theropods were closely related to the Palaeognathae “old jaws” bird family. Extant palaeognath birds include the flightless Kiwi, the Ostrich and the Rhea as well as volant forms such as Tinamou birds. It is now known that the Caenagnathidae family of non-avian dinosaurs are not closely related to palaeognaths.

Caenagnathids are confined to the Late Cretaceous of Asia and North America. They tend to have small heads, long necks and short tails.

*Time-calibrated Oviraptorosauria clade consensus tree showing the position of Eoneophron infernalis. Picture credit: Atkins-Weltman et al.*

Challenging Phylogenetic Assessment

Whilst the fragmentary nature of most caenagnathid specimens makes phylogenetic assessment challenging, in the recent Eoneophron infernalis paper the researchers undertook a time-calibrated phylogenetic analysis of the Oviraptorosauria. Eoneophron was placed as a sister taxon to Citipes elegans and Elmisaurus rarus.

The difficulties involved in classifying oviraptorosaurs is exemplified by this placement. Although skeletal similarities between these three dinosaurs exist, there is a lack of comparable fossil material to study. Citipes elegans is geologically older. Its fossils come from the Dinosaur Provincial Park Formation of Alberta (Campanian faunal stage of the Late Cretaceous). In contrast, Elmisaurus rarus probably predates Eoneophron infernalis by a couple of million years. It too is from the Maastrichtian faunal stage of the Cretaceous. However, E. rarus fossils come from the Nemegt Formation of Mongolia.

A revision of already described specimens coupled with improved fossil sampling should help palaeontologists to gain a better understanding of the taxonomy of the Oviraptorosauria and specifically the enigmatic Caenagnathidae.

The Oviraptorosauria clade* also includes some other theropods regarded as basal members of this clade. For example, Incisivosaurus gauthieri from the Early Cretaceous of China.

Visit the Everything Dinosaur website: Everything Dinosaur.