Queensland Farmer Discovers Kronosaurus Jaw Fossil

A Queensland farmer, out spraying weeds on his farm near Nelia in the north-western part of the State, has unearthed the fossilised remains of the lower jaw of a huge marine reptile known as a Kronosaurus.  Although the jaw measures 1.6 metres long, it came from a sub-adult, most of the teeth may be missing, but this is one of the best preserved pliosaur jaws found anywhere in the world.

Kronosaurus

Robert Hacon of Euroba Station, was taking advantage of the recent rains that have occurred in this drought hit part of Australia to spray some prickly Acacia plants when he noticed some shiny objects in amongst the weeds.  At first, he dismissed them thinking that they were fossilised mussel shells, which are relatively common in this part of the world, evidence to support the idea that much of the land mass we call Australia was part of a warm, tropical, shallow sea back in the Early Cretaceous.

However, curious to find out exactly what the objects were, he returned to the spot a few minutes later and discovered that the recent downpour had exposed a near complete lower jaw bone of a huge marine reptile.

Dr Timothy Holland (Kronosaurus Korner) Poses Next to the Fossil Jaw

Dr Timothy Holland provides a scale next to the massive Kronosaurus jaw.

Picture credit: Patricia Woodgate

An Apex Marine Predator

The first fossils of this apex, marine predator were discovered in Queensland in 1889.  At the time, the fragmentary remains were identified as a type of ichthyosaur, but in 1924 they were reassigned to the short-necked Suborder  of the Plesiosauria, the Pliosauroidea.

Most of the fossil material related to the two species of Kronosaurus so far described, have been crushed, severely weathered and distorted, but pliosaurid specialist, Dr Timothy Holland of Kronosaurus Korner, a museum that exhibits a number of marine reptile fossils found in Queensland, stated that this specimen was one of the best found to date.

An Illustration of Kronosaurus (K. queenslandicus)

A fantastic replica of the huge marine reptile Kronosaurus.

Picture credit: Everything Dinosaur

The picture above shows a superb model of the marine reptile Kronosaurus (Safari Ltd).  This replica is part of the now retired Carnegie Collectibles model series.

To see more prehistoric animals in the Safari Ltd model range: Wild Safari Prehistoric World Models and Figures.

Fossil Donated to the Kronosaurus Korner Museum

The fossilised jawbones have been donated to the Kronosaurus Korner museum, they will shortly be put on display to the public.

Commenting on the fossil find, Dr Holland stated:

“The scary thing is that this creature wasn’t even an adult when it died, it still had a lot of growing to do.  We are thrilled to display the specimen, it’s a timely reminder of Australia’s rich geoheritage and I marvel to think what else lies waiting to be found.”

The skull of this ancient marine reptile made up about a quarter of the animal’s entire body length, a spokesperson from Everything Dinosaur commented on the excellent state of preservation and estimated that the total length of the animal would have been approximately seven metres.

A Close up of the Beautifully Preserved Jaw Bones

Some teeth can still be seen in the rounded sockets.

Picture credit: Patricia Woodgate

Strong Jaws

Posterior parts of the jaw are up to eighteen centimetres thick, indicating that this powerful predator had very strong jaws.  It was most likely the top predator in the marine environment, eating fish, cephalopods and other reptiles.

Over the last few years, Everything Dinosaur has reported on a number of marine reptile fossil finds from Queensland, Australia.  Some of these fossils turn up in very unexpected places, such as the case of ichthyosaur fossil bones being found in the vegetable patch of a school.

To read more about this amazing discovery: Marine Reptile Fossils Found at School.

In Everything Dinosaur’s fossil and palaeontology predictions for 2015, we predicted that there would be some exciting new dinosaur discoveries reported from Australia.  This is certainly an exciting fossil find, but Kronosaurus was not a member of the Dinosauria.  Still, more than half of the year to go so we have plenty of time left to be proved right (just for once).

To see the full list of Everything Dinosaur’s predictions: Everything Dinosaur’s Palaeontology and Fossil Predictions for 2015.

Saurornitholestes sullivani – Don’t Turn Your Nose Up When It Comes To The Dromaeosaurids

Steven Jasinski, a PhD student at the University of Pennsylvania (Department of Earth and Environmental Science), has identified a new species of North American dromaeosaur, one that may have had a very keen sense of smell.  Saurornitholestes sullivani was not the largest predator known from that ecosystem, but with its sharp senses, grasping arms, turn of speed, large claws and jaws full of dagger-like teeth it was very probably a formidable hunter.

 Saurornitholestes sullivani 

Steven made the discovery whilst studying cranial elements (skull fossils) that had been assigned to the genus Saurornitholestes but to another species, (S. langstoni).  Up until now, Saurornitholestes langstoni was the only species assigned to this genus, now there are two.  This is yet another example of a new dinosaur species being erected from a reassessment of previously described fossil remains.  The Saurornitholestes genus was established in 1978, following the description of a partial skeleton discovered in Alberta (Canada).  Although, no complete or near complete fossil specimen has been found to date, fossil material from both the Judith River Formation (Montana) and the Dinosaur Provincial Park Formation (Alberta) have been assigned to this genus.

The huge number of broken teeth found, indicate that this dinosaur was probably one of the most common predators in this part of North America approximately 75 million years ago (Campanian faunal stage).

An Illustration of a Pair of S. sullivani Attacking a Juvenile Parasaurolophus

Fearsome predator of the Late Cretaceous.

Picture credit: Mary P. Williams

 The picture above depicts a pair of feathered dinosaurs attacking a juvenile duck-billed dinosaur.

A Feathered Dinosaur

Although no evidence of feathers have been found preserved alongside fossil material assigned to this genus, it is likely, that this small, agile dinosaur was feathered.  A report on Saurornitholestes sullivani has been published in the New Mexico Museum of Natural History and Science bulletin.

The fossil material was originally found by American palaeontologist Robert Sullivan in 1999, when a field team was exploring the Bisti/De-Na-Zin Wilderness in northern New Mexico.  The fossils were initially described as Saurornitholestes langstoni and represented the southernmost location for this species.

Differences in Skull Anatomy

However, Steven Jasinski conducted a comparative analysis of these fossils with those of S. langstoni from Montana and Alberta and he observed a number of differences in skull anatomy.  When the brain shape and volume was calculated, the student noted that the proportion of the brain dedicated to interpreting and analysing smells was unusually large.  The enlarged olfactory bulb indicates that this two-metre-long dinosaur had a powerful sense of smell.

Jasinski commented:

“This feature [enlarged olfactory bulb] means that Saurornitholestes sullivani had a relatively better sense of smell than other dromaeosaurid dinosaurs including Velociraptor, Dromaeosaurus and Bambiraptor.  This keen olfaction may have made S. sullivani an intimidating predator as well.”

 Steven Jasinski Holding a Replica of the Skull and Upper Jaw of S. sullivani

Student Steven Jasinski.

Picture credit: University of Pennsylvania

The picture above shows Steven holding a replica of the fossil material, the large eye socket (orbit) also suggests that this little hunter had keen eyesight.

Saurornitholestes sullivani from Southern Laramidia

At the time S. sullivani lived, North America was split into several parts separated by an inland sea (the Western Interior Seaway).  This dinosaur lived on the landmass known as Laramidia.  S. sullivani represents the only named dromaeosaur from the Late Cretaceous of southern Laramida, but the wealth of micro-fossil evidence, consisting of broken teeth suggests that there may have been several different species of dromaeosaur inhabiting the floodplains on the eastern shores of Laramidia.

Although a distinct species, Saurornitholestes sullivani was very closely related to S. langstoni.  Finding two distinct species of this genus hundreds of miles apart supports the hypothesis that distinct but closely related megafaunal communities existed on Laramida (supporting the concept of ethnicity within the Dinosauria of Late Cretaceous North America).

Approximate Location of Saurornitholestes Fossil Material from Laramidia

Saurornitholestes fossil material mapped.

An Exceptional Sense of Smell

Having an exceptional sense of smell would have helped this agile dinosaur to sniff out potential prey.  Although, in the illustration above Saurornitholestes is depicted attacking a duck-billed dinosaur, it may not have hunted large prey.  The sense of smell could have helped this dinosaur, that probably measured around one metre high at the hips, to sniff out mammals living in burrows or to find lizards and other small creatures in the undergrowth.  In addition, an acute sense of smell could have helped Saurornitholestes find carrion that it could then scavenge.

The Beasts of the Mesozoic series of articulated models includes Saurornitholestes figures: Beasts of the Mesozoic Articulated Models.

Early Birds from the Early Cretaceous

Researchers from the Chinese Academy of Sciences have published information about a new species of ancient bird which suggests that the clade of Aves that produced today’s modern feathery friends, the Ornithuromorpha was around at least five million years earlier than previously thought.  The new species comes from strata that is estimated to have been laid down around 130.7 million years ago (Barremian faunal stage of the Early Cretaceous).  This new type of early bird, named Archaeornithura meemannae has been described from two beautifully preserved fossils (mostly, see below), discovered in the Protopteryx horizon, part of the Huajiying Formation (Sichakou basin, Fengning County, Hebei, north-eastern China).

 Archaeornithura meemannae

 Archaeornithura meemannae – A Very Early Bird

Archaeornithura meemannae – believed to adapted for wading.

Picture credit: Institute of Palaeontology and Palaeoanthropology (Beijing)

The picture shows an artist’s illustration of this little bird that measured around fifteen centimetres in length.  The fossil has been preserved in fine-grained volcanic sediments and much of the plumage surrounding the delicate bones can still be seen.  Sadly, the skull and neck bones are not well preserved in either specimen and the researchers have been unable to confirm whether this bird had teeth in its jaws or not.  However, writing in the academic journal “Nature Communications”, the scientists identify this creature as the earliest known example of the Ornithuromorpha, the branch of the bird Order that led to the Neornithes (modern birds).

The previous earliest known example of a member of the Ornithuromorpha dates from rocks around 125 million years ago, this fossil too, was found in China.

The Holotype Fossil of  Archaeornithura meemannae

The slab and counter slab showing the holotype.

Picture credit: Nature Communications

Early Birds

The picture above shows the slab (left) and the counter slab (right) of the holotype fossil, which like the second specimen is part of the vertebrate fossil collection at the Tianyu Museum of Nature (Shandong Province, China).

These early birds should feel very much at home at the museum, as it houses one of the most extensive collections of vertebrate fossil material excavated from Lower Cretaceous sediments in the world.  The binomial name Archaeornithura meemannae comes from the Greek “Archae” for ancient and “Ornithura”, so the genus name means “ancient Ornithuromorph”.  The species name honours Dr Meemann Chang in recognition of her work in the study of the Jehol Biota.

The environment of this part of north-eastern China during the Early Cretaceous was one of a sub-tropical climate, dominated by extensive forests interspersed by numerous large bodies of fresh water. The absence of feathers on the legs of A. meemannae and the long legs has led to speculation that this bird may have lived in a lacustrine habitat and been adapted to a wading life-style.

Little is known about the skull, so the diet can only be guessed at, but perhaps this ancient bird ate insects or pecked at water plants.  Although the research team cannot be certain, it has been stated that this early bird was not that interested in catching worms, as the proverb goes,  but it probably was a herbivore.

Ancient Bird

The Remarkably Well-Preserved Plumage (Wings)

A close up of the feathers on the wings.

Picture credit: Nature Communications

The picture above shows:

a). Left wing main slab holotype

b). Right wing main slab holotype

c). Feathers on the remnants of the head and neck

d). Alular feathers on the left digits with one very clearly visible wing claw.

Feather Adaptations

Alular feathers are found on the leading edge of the wings of birds (they are also associated with the limbs of some feathered dinosaurs, we think).  They help direct air over the upper surface of the wing, thus improving control and lift.  More primitive birds such as the confuciusornithids lack these feather adaptations.  Ornithuromorpha are believed to have comprised about half of the bird species that lived during the Mesozoic, the descendants of some of these birds from the Ornithuromorpha clade survived the Cretaceous mass extinction and evolved into modern birds.

The other major bird clade of the Mesozoic Era was the Enantiornithes, although common, this group died out and are not directly ancestral to modern birds.

Co-author of the study Wang Min (Chinese Academy of Sciences) stated:

“The new fossil represents the oldest record of Ornithuromorpha.  It pushed back the origination date of the Ornithuromorpha by at least five million years.”

To the casual observer, if you had travelled back in time to view Archaeornithura meemannae, it would have looked very similar to modern wading birds, except for the small claws visible on its wings.

The Chinese scientists conclude that by around 130 million years ago a number of avian lineages had already evolved and that it was quite likely that the Aves rapidly diversified during the early part of their evolutionary history.

PNSO have included models of several feathered theropods in their “Age of Dinosaurs” replica range: PNSO Age of Dinosaurs Models.