Dicynodont with a Big, Bulbous Nose – Bulbasaurus phylloxyron

The Karoo Basin of South Africa is famous for its Permian fossils.  The rocks exposed in this part of the world, trace the geology of what was to become known as the super-continent of Gondwana, from the Late Carboniferous through into the Early Jurassic.  It is the abundance of Permian-aged tetrapod fossils from the Beaufort Group of strata and its rock formations that have provided palaeontologists with a great deal of information about terrestrial life before the rise of the dinosaurs.

Researchers from the Museum für Naturkunde Berlin and the University of Witwatersrand have announced the discovery of a bizarre-looking new type of dicynodont, this critter may have been quite small, but it did have large tusks and strange, rough boss on its nose.

An Illustration of the Newly Described Late Permian Dicynodont Bulbasaurus phylloxyron

A drawing of the new Late Permian Dicynodont Bulbasaurus.

Picture credit: Matt Celeskey

Bulbasaurus phylloxyron

Described from skull material that was discovered preserved in 1.5 metre-deep mudstone, it is thought the head of this reptile was transported by a flood event before coming to rest in the mud.  Over millions of years the mud became rock, preserving the skull and some of the teeth, including evidence of an impressive pair of tusks (located in the upper jaw).

Photographs of the Holotype Skull Material in Situ (SAM-PK-K11235)

The skull of Bulbasaurus photographed by a member of the field team.

Picture credit: Peer J

The photograph above shows two views of the holotype material (SAM-PK-K11235) taken from the excavation site.  Picture (A) shows the skull in left lateral view, whilst (B) shows the dorsal view.  The geological hammer provides scale.

A Bizarre Permian Dicynodont

The fossil material was discovered at Driekoppe, Vredelus, Fraserburg, Western Cape Province, by Dr Roger Smith (University of Witwatersrand), it was during a visit to view the collection of Permian fossils that dicynodont specialist Dr Christian Kammerer (Museum für Naturkunde Berlin), noted the skull showed a number of unusual features, most of which are associated with much younger types of Dicynodontians.  Further study led to the establishment of a new species (B. phylloxyron).  The genus name means “bulbous nose”, a reference to the large and roughened boss located on the naris bone.

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Left lateral view and line drawing of the skull of Bulbasaurus.

Picture credit: PeerJ with annotation by Everything Dinosaur

The picture above shows a photograph of the sixteen-centimetre-long skull and an accompanying line drawing.  The large, bulbous area of the naris (from which this animal has been named), is highlighted.

Key

sq = squamosal, qj =quadratojugal, apt = anterior pterygoid ramus, ec = ectopterygoid, fr = frontal, la = lacrimal, mx = maxilla, na = nasal, pmx = premaxilla, pb = base of postorbital bar, po = postorbital, prf= prefrontal and ? indicates an unidentified bone.  The area shaded grey in the line drawing represents matrix.

For models and replicas of prehistoric animals including Permian creatures: CollectA Deluxe Scale Prehistoric Animal Models.

A Significant Permian Fossil Discovery

Bulbasaurus was found in rocks that have been dated to the early Lopingian Epoch of the Late Permian.  It lived around 259 million years ago.  The fossils are significant as Bulbasaurus is the oldest known member of a family of dicynodonts known as the Geikiidae.  Its discovery helps to fill in a gap in the early fossil record of this important group.

The scientific paper: “An early geikiid dicynodont from the Tropidostoma Assemblage Zone (late Permian) of South Africa”, published in the journal PeerJ.

Visit the award-winning, user-friendly Everything Dinosaur website: Everything Dinosaur.

Saccorhytus coronarious – Our Earliest Ancestor?

It might resemble that green, slimy ghost/monster out of the movie Ghostbusters, but this tiny sack-like creature with a huge mouth (and no obvious signs of an anus), might just be our earliest ancestor.  Scientists writing in the journal “Nature” report on the discovery of Saccorhytus coronarious a tiny organism less than one millimetre in diameter that could represent the oldest “deuterostome” yet discovered.  Deuterostomes are divided into three major clades, one of which is the Chordata, that’s the vertebrates which includes us!  This animal could represent your earliest known ancestor!

An Illustration of the Minute Saccorhytus coronarious – Our Earliest Ancestor?

An illustration of the earliest known deuterostome – Saccorhytus.

Picture credit: Cambridge University

Deuterostomes

Within the Animal Kingdom (Animalia), the complex organisms, (more complex than jellyfish with their radial symmetry), are split into two main groups namely:

1. Deuterostomia – bilateral symmetry mainly, with only the echinoderms showing radial symmetry, this group includes all the Chordata, plus the Hemichordata – acorn worms and the extinct graptolites and the Echinodermata star fish, sea urchins etc.
2. Protostomia – bilateral symmetry including the molluscs, arthropods, nematodes and worms.

These lineages are believed to share a common ancestor that lived during the Ediacaran geological period.  The hunt has been on to find this common ancestor, and Saccorhytus is the best candidate discovered to date.  Firstly, it is the most primitive example of a deuterostome yet discovered and it is the oldest, having been discovered in rocks laid down some 540 million-years-ago (Fortunian Stage of the Lower Cambrian).

Saccorhytus coronarious

The micro-fossils were discovered in rocks in Shaanxi Province, (central China) and when it comes to identifying vertebrate features, that is a bit tricky, despite the remarkable degree of preservation.

A Highly-Magnified Image Showing the Micro-fossil (S. coronarious)

A highly-magnified image of Saccorhytus.

Picture credit: Jian Han

The body is bag-like and has a huge, mouth located in the centre (the oval shaped object in the central part of the organism).  It has four conical openings on either side of the body, that may well have served as outlets to allow sea water that had passed into the body to be ejected.  It has been suggested that these simple openings could provide an insight into the origin and development of gills.

The Mouth of Saccorhytus coronarious Probably Served Two Functions

The mouth probably served two functions, as the researchers have not been able to detect the presence of an anus.  What entered into the mouth, once nutrients had been extracted, was ejected out of the mouth.  The organism does show bilateral symmetry, however, a trait that was passed onto all the vertebrates.

Living in the Sand

Saccorhytus could have easily sat on the head of a pin.  It probably lived between grains of sand on the seabed, wriggling its way through them, perhaps it was an active predator, perhaps it fed on waste or other detritus.  The study was carried out by an international team of academics, including researchers from the University of Cambridge in the UK and North-west University in Xian China, with support from other colleagues at institutions in China and Germany.

Simon Conway Morris, Professor of Evolutionary Palaeobiology and a Fellow of St John’s College, University of Cambridge, one of the co-authors of the study, commented:

“We think that as an early deuterostome this may represent the primitive beginnings of a very diverse range of species, including ourselves.  To the naked eye, the fossils we studied look like tiny black grains, but under the microscope the level of detail is jaw-dropping.  All deuterostomes had a common ancestor, and we think that is what we are looking at here.”

Fossils Show a Wide Degree of Diversity and Variety

Most of the very early deuterostome groups are known from fossils that date from between 510-520 million years ago, but these fossils already show a wide degree of diversity and variety so, if they did share a common ancestor, it probably lived much earlier. What the common ancestor might have looked like has also been extremely difficult to work out, given the level of diversity and variety already found in the fossil record from 510-520 million years ago.

The scientific paper: “Meiofaunal deuterostomes from the basal Cambrian of Shaanxi (China)”, published in the journal “Nature”.

Visit the Everything Dinosaur website: Everything Dinosaur.

Robust Necks Indicate Apex Predator Niche

Amongst all the amazing genera that are now grouped into the Order Pterosauria, it is perhaps, the azhdarchids that are the most spectacular of all the pterosaurs.  When other types of flying reptile were in decline and heading towards extinction in the Late Cretaceous, the Azhdarchidae were still going strong.  Some of these Late Cretaceous azhdarchids, animals such as Quetzalcoatlus, Arambourgiania and Hatzegopteryx stood as tall as a giraffe and had wingspans the size of small aircraft.  These large wings, combined with their light bodies (even the very largest are estimated to have weighed no more than 225 kilogrammes), permitted these creatures to fly extremely long distances.

Studies of wing function and biomechanics indicate that some of the largest forms could have traversed continents and crossed the recently formed Atlantic Ocean with ease.

A Model of the Giant Late Cretaceous Azhdarchid Pterosaur Quetzalcoatlus (Q. northropi)

A model of the giant Pterosaur Quetzalcoatlus.

Picture credit: Safari Ltd

The picture (above) shows a Quetzalcoatlus model from the range produced by Safari Ltd.

To view this range: Wild Safari Pterosaur and Dinosaur Models.

To read an article about the flight dynamics of giant Cretaceous pterosaurs: Cretaceous Runways – Flight Dynamics of Pterosaurs.

Which Niches within Ecosystems?

Our understanding of the Pterosauria has been much revised over the last three decades or so.  Recent fossil finds and new research on previously collected and catalogued material has provided a wealth of scientific information and a new paper written by the eminent British pterosaurologists Darren Naish (University of Southampton) and Mark Witton (University of Portsmouth), further supports the hypothesis that some super-sized pterosaurs occupied apex predator niches within Late Cretaceous ecosystems.

A study of two pterosaur neck bones (cervicals), including one giant, twenty-four-centimetre-long cervical suggests that the body proportions of azhdarchids may not have been as uniform as previously thought.

The researchers postulate that the enormous Hatzegopteryx had a proportionately shorter, more stocky neck that was very strong.

Pterosaurs with Strong Necks

Line Drawings Showing Various Views of the Giant Azhdarchid Pterosaur Fossil (EME 315)

Giant azhdarchid cervical vertebra referred to Hatzegopteryx sp. (A–D) line drawings of EME 315 in anterior (A) right lateral (B) ventral (C) and dorsal (D) views.

Picture credit: PeerJ

In the picture above, four views of the pterosaur neck bone are shown (A) viewed from the front, (B) viewed from the right, (C) viewed from underneath and (D) viewed from the top.  The lighter areas in the drawings indicate where damage to the bone has occurred, the darker shading indicates the presence of filler.  Scale bar equals ten centimetres.

A strong, powerful neck would have been resistant to the forces and stresses imposed upon it by a prey struggling in the pterosaur’s large beak.  The specimen (EME 315) is almost as wide as it is long and as it was excavated from the Maastrichtian Sebeş Formation of the Transylvanian Basin, (Romania), it has been assigned to the Hatzegopteryx genus, as Hatzegopteryx thambema fossil material is known from the adjacent and contemporaneous Densuş-Ciula Formation, of the northern Haţeg basin.

Thick, Robust Neck Bones Support the Idea of Pterosaurs Feeding on Dinosaurs

The scientists compared the dimensions of EME 315 (believed to be cervical VII, which is from the base of the neck, articulating with the first of the thoracic or dorsal vertebrae), to the neck bones from other azhdarchids and they argue that in the absence of large, terrestrial predators on the ancient island, known as Hateg, azhdarchids such as Hatzegopteryx occupied the role of top predators in the ecosystem.

The Robust and Relatively Short Neck of Hatzegopteryx Helps this Pterosaur Overcome a Struggling Dinosaur

Transylvanian giant azhdarchid pterosaur Hatzegopteryx sp. preys on the rhabdodontid iguanodontian Zalmoxes.

Picture credit: Mark Witton

Azhdarchid Pterosaurs Had Huge Skulls

Azhdarchids had proportionately bigger skulls than any other known terrestrial vertebrate.  Their size and these huge skulls, if related to a relatively, short but powerful neck would lend support to the idea that these creatures stalked smaller animals in the same way that extant Marabou storks (Leptoptilos crumenifer) do in Africa.  However, unlike the modern Marabou, which catches frogs, lizards, small mammals and fish, Hatzegopteryx would have been capable of swallowing whole a dinosaur the size of a Cocker Spaniel!

Hatchling dinosaurs would have been especially vulnerable to attack and with a number of dwarf dinosaur forms known from the Hateg Formation (Magyarosaurus), juveniles could have been predated upon also.

Giant Azhdarchid Neck Bone (EME 315) Compared to Arambourgiania Giant Cervical

The giant neck bone compared to the only other giant pterosaur cervical Arambourgiania.

Picture Credit: PeerJ

Cervicals Compared

Writing in the journal “PeerJ” the researchers compare the Hatzegopteryx cervical (cervical VII), with the only other giant azhdarchid neck bone known, a single cervical representing Arambourgiania philadelphia, from the Late Cretaceous of Jordan (see picture above).  The paucity of the fossil record restricts accurate size estimates for entire animals, but the cervical assigned to A. philadelphia, believed to represent cervical V is approximately seventy centimetres long.  Its morphology and proportions are very different from the Hatzegopteryx material (EME 315).  This suggests that there may be greater variation in the body proportions of the Azhdarchidae then previously thought.

Some members of the Azhdarchidae may have had shorter and stronger necks than other genera.  This leads to the tantalising idea that, giant pterosaurs did indeed occupy apex predatory roles in isolated island ecosystems such as Hateg, which was largely devoid of large, carnivorous theropods and that proportional differences between super-sized taxa may even hint at distinct feeding specialisms.

Late Cretaceous Jordan Two Arambourgiania Fight Over a Luckless Dinosaur

Arambourgiania philadelphia (giant pterosaurs) squabble over a small Theropod dinosaur.

Picture credit: Mark Witton

Giant Pterosaur Scavengers?

If we reflect on the feeding habits of the Marabou stork, it is known to feast on carrion.  Few carnivores will turn up the offer of a free meal if they find a corpse to feed on.  It could be speculated that some of the more robust-necked azhdarchids may have specialised in scavenging the carcases of dinosaurs.

The absence of teeth in the jaws, may have inhibited these reptiles from being able to eviscerate a dead dinosaur, but this could have been compensated to some degree by having a strong, pointed beak and a powerful neck.  As well as being apex predators, some Late Cretaceous pterosaurs may have occupied an ecological role similar to today’s vultures.  Ironically, when Quetzalcoatlus northropi was first named and described back in 1975, several palaeontologists argued that this giant flying reptile filled a scavenger niche.

For an article which examines the role of Azhdarchid pterosaurs in ecosystems (based on research published in 2015): Understanding Azhdarchid Pterosaurs.

The article: “Naish D, Witton MP. (2017) Neck biomechanics indicate that giant Transylvanian azhdarchid pterosaurs were short-necked arch predators”.  PeerJ 5:e2908, (published in the online journal PeerJ).

To read the PeerJ article: Peer J Article.

Visit the Everything Dinosaur website: Everything Dinosaur.