Friday, 28 February 2014

Monster iguanodontoids


  
Pula, Istria, Croatia, late Albian (mid-Cretaceous)

About a 100 million years ago, the beaches near the city of Pula (which itself has about 3000 years long history) were sandy and muddy and the sea was shallow. The rudist clams formed some sort of rudist reefs not far from the coastal line. The stromatolites colonies were sticking out of the water, while the large sturgeon or/and guitar fish probed the mud for food swimming the shoals. Small, large and huge dinosaurs, crocks, monitor lizards and pterosaurs left their footprints in the wet sand and sticky mud.
  Many years later, the old beaches turned into multilayer limestone rock, looking like some sort of a giant book. The ancient archives with the notes of the the life long gone,waiting for the sea to uncover them and somebody interested and inquisitive to read the fossil "hieroglyphs".

Here are the pes footprints of the immensely large iguanodontoid. I am standing on the convex  left pes with infilling, while photographing the concave right pes (footprint) in an oblique view. My yellow outline marks the impression. The displacement rim is quite nicely visible, as well as the mud suction traces along the mid line. Each of the prints measure unbelievable 135-145 cm in length. I don't think there was a larger iguanodontoid print discovered anywhere in the world, so far. Yet, these prints are situated on one of the most popular and crowded beaches near Pula. I've stepped over these prints so many times myself over the years without noticing them. Why? Simply because they were so enormous, that they were too difficult to spot and figure out as once belonging to a living, breathing animal. The ornitischian who left them in the wet sand must have measured at least 18 to 20 meters in length! (See the comparative sizes in my banner)





Tuesday, 25 February 2014

Giant ankylosaurs


  Here are the pes footprints of the two giant ankylosaurs (not to scale) with my interpretations on the right:
Pula Albian (mid-Cretaceous) ankylosaur right pes lenght: 85-95 cm (A, B) - I am standing on it's toe #5 of it's four pes toes;
Tumbler Ridge (Canada) late Cretaceous anky has a scale of 10 cm for size comparison (about 44 cm total pes length) (E, F) Photo credit: Rich McCrea. 

 I know it sounds unbelievable, but the Pula ankylosaur, as derived from the size of the largest pes footprints (there are at least 6 of the foot impressions at the Pula site) must have measured some 14-16 meters in length (!)  In a way it wasn't that surprising to me, since all of the super mega fauna members from Pula site were world record holders. Check out my title banner: these are the ultra dinosaurs from Pula in scale (!) They were gregarious, as it seems from the fossil record. Maybe comprising of small family groups. A pair or more adult dinosaurs guarding and taking care of their offspring.
It is interesting that some members of  Thyreophora - a subgroup of the ornithischian dinosaurs
which include well-known suborders Ankylosauria and Stegosauria, had diverse number of toes.
While some of the ankylosaur ichnogenera had three, the others had four toes on their hind feet.
Thus it is possible to miss identify the thyreophoran three-toed pes tracks for iguanodontoid ones and vice versa, especially if the front feet impressions are missing or are poorly preserved. Despite of the enormous record size of the Pula, Istrian tracks it is less likely that these were artifacts.

The Tumbler Ridge site


Monday, 24 February 2014

Late Cenomanian theropod tracks


  Last year (2013) I finally visited the track site situated on an Istrian natural reserve park the cape "Kamenjak". There are Late Cretaceous (late Santonian) dinosaur tracks all over the place, but the best preserved are on the Grakalovac promontory, on the beach, near the entrance to the park.

A nice medium-sized theropod trackway is marked with ugly black circles (A). My interpretation (B). However, there are more theropod footprints scattered all around. See one in filled with the sediment (C) and my interpretation with a couple of more less preserved prints (D).
The larger tracks that nobody could identify so far, are also marked with black circle. They seem to me like the prints of a fairly large ankylosaur. More about it in the next post.


The Italian paleontologist Fabio Marco Dalla Vecchia wrote extensively on the dinosaur fossils in Istria. Here is one of the papers.


Sunday, 23 February 2014

Ankylosaur tracks


 From 2010-2012 I have also discovered a few ankylosaur tracks near Pula. There were even possible baby ankylosaur prints. However, the most impressive are the giant pes footprints measuring some 75 cm in length. In the pictures below are a couple of nicely preserved ones, left by somewhat smaller individuals. However they were still large by any standards. Compare the tips of my shoes for size. The ankylosaur was probably similar to Polacanthus or Sauropelta. The upper images apparently represent the right pes, while the lower ones feature the left pes.


Compare to some of the footprints from Tumbler Ridge. See the Anky trackway
More tracks.


Saturday, 22 February 2014

More on sauropod tracks


 In 2009 I have discovered one of the dinoturbated sites near Pula. Since that time, I managed researching several more similar sites along the beach there. In the picture is a suropod footprint (Brontopodus sp.) that was surprisingly well preserved in 3D. You probably remember playing in a wet sand as a kid. The sand had to be wet and of the precisely right consistence and you had to be very careful while making a cast of your plastic dish or it would have collapsed right away. The sauropod cast was originally a negative footprint, that served as a mold. It was filled in with the sediment ( wet rudistic sand) brought by a rising tide, after the original substrate containing the impression dried and hardened a bit. Both sediments were eventually buried under more sediments and lithified.
In recent times, the sea eroded off the upper sedimenst freeing the cast.



The mid-Cretaceous (late Albian) subadult sauropod (titanosaur) right hind footprint cast (positive) from the dinoturbated beach area, which is full of tourists in the Summer time (A).  The same print in false colours to enhance the shape (C). My interpretative drawing of the impression (D).
The negative of the left hind sauropod footprint, which was probably left by the same animal and was the part of the same trackway. The little black bag measures 13cm in length (B).
The adult animal had a foot that measured some 140 cm in length.
 

Thursday, 20 February 2014

A sauropod right pes on a building block



contact.html


 A sauropod right pes on a building block of the Early Cretaceous limestone at the pier near Pula (Istria, Croatia)



I don't remember if I said it before, but Istria has been literary "littered" with the Mesozoic fossils. The dinosaur tracks can be considered as numerous and omnipresent. Which doesn't mean they are easy to find by laymen. One has to learn distinguishing them from common artifacts. The limestone erosion is prone to forming very rich array of shapes.

So, here I am, walking along the beach and looking for some familiar shapes. I get awarded quite often. Here is a nice sauropod (probably a titanosaur) right hind foot print on a building block. The production process in the quarry left it in a rather good shape. Although, the block looks slightly "flawed" because of the dinosaur impression. The photograph was taken on February 15th 2014. Red outline helps you visualise the print. There is a low displacement rim in front of the track, where it should be. The pes measures about 60 cm in length, representing a decent size track maker sauropod. The largest sauropod hind footprints I've found there measure about 130-140 cm in length. Those were true giants! 

Finding dinosaur tracks on building blocks is not that rare either. I've found many myself. Some of the tracks were found by Dalla Vecchia, as described in his paper.






Tuesday, 11 February 2014

Nodosaur and possibly Rhabdodon finds in Quarry Stranice near Slovenske Konjice (repost from BDW 2005)

contact.html Home  
Triceratops by BeriMimi


Mesozoic Mosaic pg #5

Illustration: Sauropelta - by Beri (graphite), Copyright © 2004-2005 Berislav Krzic
 
Mesozoic Mosaic pg #5


Photograph of Struthiosaurus austriacus (Bunzel 1870) fossil on display in Natural History Museum in Vienna
Site: Muthmannsdorf near Wiener Neustadt, Austria


Struthiosaurus might look like a cross between Edmontonia and Sauropelta, says Kenneth Carpenter, Ph.D.

Struthiosaurus References
s:

(update 2014)

Nodosaur and possibly Rhabdodon finds in Quarry Stranice near Slovenske Konjice
 

In the sediments of Quarry Stranice (kamnoloma Stranice) near SlovenskeKonjice (Campanian; gosauski razvoj) in north-east Slovenia, fossils of single and colonial corals were found. In addition to the corals, bivalves, fragments of sponges, snail shells, ostracodes, briozoa, algae and foraminifera were also found. On the west side of the site, near Lipa, fragments of fish teeth, a crocodylian tooth and
the long bones of dinosaurs were discovered. These fossils were first found in 1999 by Franc Pajtler, and researched by Dr. Irena Debeljak. Dr. Debeljak (ZRC SAZU) thought the bones possibly belonged to a medium-sized quadrupedal plant-eating nodosaur, which was a member of the family Ankylosauria. This is the second discovery of dinosaurs in Slovenia. The first one, near Kozina, was in an area that was separated from Quarry Stranice in the Upper Cretaceous by the sea, precluding a comparison of the fauna from the two sites. The fossils of dinosaurs, crocodylians, turtles and freshwater fish indicate a rich vertebrate fauna at that time. The nearest site to Stranice with nodosaur remains is in the vicinity of Vienna (Muthmannsdorf -Wienerneustadt, Avstria). The locality of Quarry Stranice (kamnoloma Stranice) near Slovenske Konjice thus becomes an important palaeontological find.
The fossils are on display in the Natural History Museum in Ljubljana:
http://www2.pms-lj.si/oddelki/paleontologija/stranice.html

English translation: Berislav Krzic

Edited by: Brian Franczak

Note (Feb/2014): as to my knowledge, up to this day, no further research has been conducted regarding the Quarry Stranice fossil finds.
 


BOOK STORE
.
Mimi

Dinosaurs vs.people




No, I haven't suddenly turned creationist. Of course, the earliest hominids evolved some 60 million years after the dinosaurs went extinct (if we don't count the birds as dinosaurs). This is an illustration for my time travel science fiction novel years ago. The novel is still unfinished.






Monday, 10 February 2014

My old article from BDW on Huaxiagnathus

contact.html Home  

Triceratops by Beri


Mesozoic Mosaic pg #3
Huaxiagnathus orientalis  by Beri Illustration of a new compsognathid, Huaxiagnathus orientalis - by Beri (graphite), Copyright © 1999-2004 BERI
Feb 2004 (updated)

Huaxiagnathus orientalis - a large compsognathid from Early Cretaceous of China
The paper was published in March, 2004 in the new Journal of Systematic Paleontology (The British National History Museum):
- Sunny H. Hwang, Mark A. Norell, Ji Qiang, Gao Keqin, 2004, A LARGE
COMPSOGNATHID FROM THE EARLY CRETACEOUS YIXIAN, FORMATION OF CHINA.
Journal of Systematic Palaeontology Volume 2 (Issue 01), 13-30.

It describes a new compsognathid, Huaxiagnathus orientalis, ( new genus and species) known from a nearly complete skeleton lacking only the distal end of the tail. At the first glance, the skull is very similar to the still unnamed new German compsognathid. Rather short forelimb has three fingers.

In the paper "Huaxiasaurus" specimen is reffered to Huaxiagnathus. Supplementary information is included and has 17 new characters added to the Theropod Working Group Matrix, and several new taxa coded in it (Shenzhousaurus, Archaeornithomimus, Ornithomimus, Anserimimus, Huaxiagnathus, Sinosauropteryx, Compsognathus, IGM 100/44).  The topology has compsognathids (Huaxiagnathus, Sinosauropteryx, Compsognathus) as maniraptorans more derived than Ornitholestes.  
Early Cretaceous, People's Republic of China, Yixian Formation, Liaoning, Yehol Group sediments.
Approximate length: 130-145cm
Pronounciation: hua-xia-NA-thus
Holotype photograph from the paper



BOOK STORE
A note (Feb 2014):

My original restoration of the theropod was done prior to the publication of the paper, based on the photographs available at the time on the www.



Mimi

Sunday, 9 February 2014

Repenomamus robustus - a large triconodont mammal from Early Cretaceous of China from BDW (2005)

contact.html Home  
Triceratops by Beri
Mesozoic Mosaic pg #4
Repenomamus robustus by Beri
Illustration of a fierce Masozoic triconodont mammal , Repenomamus robustus chasing juvenile Psittacosaurus - by Beri (graphite), Copyright ©2005 BERI
Jan 2005

MAMMALS STRIKE BACK

Repenomamus robustus - a large triconodont mammal from Early Cretaceous of China


HU, Y., J. MENG, Y. WANG & C. LI. 2005. Large Mesozoic mammals fed on young dinosaurs. Nature 433: 149-152.

"Mesozoic mammals are commonly portrayed as shrew- or rat-sized animals that were mainly insectivorous, probably nocturnal and lived in the shadow of dinosaurs. The largest known Mesozoic mammal represented by substantially complete remains is Repenomamus robustus, a triconodont mammal from the Lower Cretaceous of Liaoning, China. An adult individual of R. robustus was the size of a Virginia opossum. Here we report a new species of the genus, represented by a skeleton with most of the skull and postcranium preserved in articulation. The new species is 50% larger than R. robustus in skull length. In addition, stomach contents associated with a skeleton of R. robustus reveal remains of a juvenile Psittacosaurus, a ceratopsian dinosaur. Our discoveries constitute the first direct evidence that some triconodont mammals were carnivorous and fed on small vertebrates, including young dinosaurs, and also show that Mesozoic mammals had a much greater range of body sizes than previously known. We suggest that Mesozoic mammals occupied diverse niches and that some large mammals probably competed with dinosaurs for food and territory."

Abstract

References:

1.  Large Mesozoic mammals fed on young dinosaurs     Yaoming Hu, Jin Meng, Yuanqing Wang, Chuankui Li
SUMMARY: Mesozoic mammals are commonly portrayed as shrew- or rat-sized animals that were mainly insectivorous, probably nocturnal and lived in the shadow of dinosaurs. The...
CONTEXT: ...Cretaceous Jehol Biota from the Yixian Formation in Liaoning, China, has yielded several mammal species. Two of them, Repenomamus robustus and Gobiconodon zofiae, are from the basal member of the formation that has a radiometric......
Nature433, 149 - 152 (13 Jan 2005) Letters to Nature
Abstract | Full Text | PDF 


 2.  Mammalian palaeobiology: Living large in the Cretaceous     Anne Weil
SUMMARY: Discoveries of large, carnivorous mammals from the Cretaceous challenge the long-held view that primitive mammals were small and not so interesting. Have palaeontologists been asking the wrong...
CONTEXT: ...of questions and speculation among palaeontologists. The dinosaur-eater belongs to a species of large mammal, Repenomamus robustus, which was described first from a skull. The new specimen is more complete — and on its left side,......
Nature433, 116 - 117 (13 Jan 2005) News and Views
Full Text | PDF 


 3.  Mammal bites dinosaur     Description: 13 January 2005 Mammal bites dinosaur We tend......
CONTEXT: ...picture is changing. The extinct mammal Repenomamus robustus, discovered five years ago, broke the mould: it was much bigger, the size of a Virginia opossum. And now another member of the genus Repenomamus has been found that is......
http://www.nature.com/nature/links/050113/050113-8.html 

***


Some comments:


"Not to take anything away from the intrinsic coolness of this find, but the idea that Mesozoic mammals might have preyed on juvenile dinosaurs is hardly astonishing. Anybody familiar with the food habits of modern small mammals would have predicted it. In fact, I suggested just such a possibility way back in 1980 on pp. 70-71 of my contribution to _A Cold Look at the Warm-Blooded Dinosaurs_. What _IS_ surprising to me is just how big the bigger Mesozoic mammals seem to have gotten, at least in some faunas!"
James Farlow, Ph.D.



***"...There are at least seven teeth on each jaw quadrant of the juvenile Psittacosaurus, of which most are worn. This demonstrates that the Psittacosaurus skeleton is not from an embryo (from the paper)...""Actually, late term vertebrates are notorious for grinding their teeth, whether in a womb or in an egg, Unhatched embryos of Hypacrosaurus from Canada show worn teeth."
Ken Kenneth Carpenter, Ph.D.





Repenomamus holotype






A few notes on: Psittacosaurus sp.
Age: Lower Cretaceous, Barremian Stage, Yixian Formation
Place: Liaoning, China  


The psittacosaurids, known only from the late Early Cretaceous of Central Asia, are considered to be close to an ancestor of the horned dinosaurs. Both the parrot-beaked and horned dinosaurs possessed jaws, being curved and tapered forward and the lateral teeth highly specialised to masticate the vegetative food. Adult psittacosaurids were relatively small, up to 2 meters in length. They were probably mostly bipedal cursors although the forelimbs in these dinosaurs were relatively long and well-developed. 


Mimi


BOOK STORE


Saturday, 8 February 2014

Funny looking dinosaurs in vintage comics Part 4

Quite often, we just don't pay enough attention to the detail the comic book artists put into their artwork. I'll try to analyse a few vintage comic book covers for you. They are just packed with action and information!


"... Modern Man versus Ancient Beast!!"
A Neanderthal man carrying a "modern" sleeping beauty under his left arm is preparing to check out the deep tendon reflexes of an old and grumpy T. rex, by hitting his knee with a rather nasty looking stone axe. Another T. rex is emerging behind the palms, to help out her (his?) partner.



A wannabe T.rex monster emerging from the yellow lake to scare the small brave and unarmed  research party, consisting of two male members, one female and a couple of cute hovering robots. There seem to be something even worse than the three stories high, toothy monster that obviously intends to either eat the alive part of the team, or step on them, or both. Because the two men are staring into the other approaching danger, that is obviously, a little bit to the right and behind the "T.rex". Maybe they arrived just at the moment the asteroid was to hit the (another ) Earth (in another universe)? Thus, they will be probably saved from the T.rex, still unaware of his imminent demise, just to be obliterated by the asteroid a few moments later. Alas, one cannot escape his/her kismet.



A brave soldier pinned down to the ground by the mighty Triceratops tail has enough strength and courage to warn  Kona of a tossed grenade. The grenade is either the size of a large pineapple, or it's flying well over Kona's head. So the warning was unnecessary. Triceratops directed by the grenadier villain, smashes an American tank, of apparently very poor quality, to pulp. The other villain, riding the head of  a T. rex lookalike theropod shoots the bursts of gun-fire at the Triceratops.  He is probably angry because the animal is blocking his view towards the laying, but still alive, G-man and Kona. He just can't make a clear shot! Damned Triceratops! Drop dead!
The stone-age Kona has no problems in handling the modern-looking machine gun.