The new ankylosaur tracks discovery

When I took this photograph back in 2009 it didn't tell me much. It just looked like it might have been some unidentified dinosaur trackway. Or not. My first suspect was a sauropod, of course. This morning I was browsing through my files looking for some photographs for the text I intended publishing and something caught my eye in this image. Some of the "footprints" actually looked like if they had toes. The toes were arranged pretty much in the order like in the ankylosaur feet (Sauropelta-like): I quickly added up the simple math and it dawned to me that this little dinoturbation is in fact the part of the large ankylosaur dinoturbation for which I thought had ended a few meters away.
In my red outline you can see my interpretation of some of the tracks. Yes, these ankylosaurs were gregarious and they congregated in three size-classes. There were also some medium-sized (maybe dromaeosaur-like) and some huge theropods around.

LM = left manus; LP = left pes; RP = right pes (click image to enlarge)

More dinosaur wonders from Pula

Here is a nice, unusual, huge iguanodontoid footprint on one of Pula's beaches. Probably the left pes, missing tip half of the toe #4 impression/cast. That's one of my latest finds. The left pes track is to the right, not visible in this photo and less preserved.
The middle toe (#3) is slightly curved towards the toe #4. That feature is consistent in most iguanodontoid tracks from Pula.

The sea is just a couple of meters away. When I get tired of rocks and tracks...

Yet another dinoturbation at one of Pula's beaches

Walking along the beach in Pula, yesterday (01/11/2014) I have discovered yet another trackway outcrop. The new tracks are not the first class quality , but it is obvious that it's a dinoturbation and a few tracks can be defined. Besides the omnipresent sauropods, it seems I have found yet another intriguing footprint (the second one) that might have belonged to some "Proto-megalania" (not featured in this article).

A large dinosaur trackway (iguanodontoid or ankylosaur? Possibly under tracks or shallow tracks on a dried surface). This layer is a bit higher than the one featured above (roughly half a meter), but it is the same beach/outcrop.

I have selected this track as the best preserved one from the lower layer, but that doesn't mean I am sure about the track maker. At the site I thought I was looking at the sauropod manus-pes set. Now I am more inclined towards the tyreophoran (ankylosaur?) origin. But maybe it was an ornithopod. Anyway, I need to check out this new site again.

I have found the new dinosaur tracks again.

It seems that almost every visit I make to the Pula beaches must end with my discovery of the new mid-Cretaceous, Pula ichnofauna tracks. It happened again in September 2014.
Here is one of the outcrops with my interpretation of the probable theropod tracks. The foot length is about 30 cm.

One of Pula's outcrops.

Back to tracks

This is in fact the first iguanodontoid track I have discovered in Pula (above). My interpretation on the right (the red outline). Note the size compared to my big feet (# 46). It is Late Albian - Mid-Cretceous (about 100 mya). The same rock surface is dinoturbated mostly by large iguanodontoids and sauropods. Also, it is weathered, due to the vicinity of the open sea.

A bit smaller "Iggy" track I have discovered about a kilometre further down the beach (resort in Pula)

  A nice manus pes set track of a large pterosaur I have found on the same beach as the Iggy in the top photograph. There are three pterosaur trackways on that spot.

 A dinoturbated rock. Probably by the ankylosaurs whose trackways I have found near by. (Pula - Late Albian)

A small titanosaur left pes track. It was probably a subadult. The outcrop is heavily dinoturbated by the very large sauropods, theropods and ornithopods. Late Albian of Pula.

A poorly preserved ornithopod track

Here is another example of a "questionable" dinosaur track from Pula. According to my scale I would grade it as a poorly preserved track (***). It is not easy to spot on these weathered rocks, although it is a convex, or relief track. The natural cast. It is slightly darker colour and there are more similar prints there. In its overall shape it does remind of an ornithopod, iguanodontoid footprint of the Hadrosauropodus type, but due to the state of its preservation it may still be a theropod.
See the b/w outline of Hadrosauropodus langstoni  - Lockley et al. (2003) track at the bottom.
My interpretation is the red outline over the print in the second image.

Some of the Cretaceous hadrosaur tracks are well described in a paper. HADROSAUR FOOTPRINTS FROM THE UPPER CRETACEOUS FRUITLAND FORMATION, SAN JUAN BASIN, NEW MEXICO, AND THE ICHNOTAXONOMY OF LARGE ORNITHOPOD FOOTPRINTS SPENCER G. LUCAS1, ROBERT M. SULLIVAN2, STEVEN E. JASINSKI2 AND TRACY L. FORD

"A reconsideration of the ichnotaxonomy of large ornithopod footprints suggests that only two
ichnogenera may be valid: Caririchnium (= Hadrosauropodus) and Amblydactylus (= Iguanodontipus)."

A crummy track or an artifact: that is the question

Forgive me for paraphrasing Shakespeare's Hamlet in the heading of this post, but it all comes to that simple question when in dilemma about the true nature of a dinosaur (or any other) track.
A strict palontologist would probably discard the possible theropod footprint from the photograph below as being to crummy to make sure.

 On the other hand, a find like this is open to discussion. According to my scale I would grade it as something in between a probable track (**) and a poorly preserved track (***). However, you can't exactly see in this photograph what made me determine such a grade. I have also found other similar prints on that particular very weathered layer, plus possible prints of a sauropod and a crock, and several prints left by the pterosaurs. All of them are rather poorly preserved, except one particular manus pes set from a rather large pterosaur. Even more: that pterosaur track is a part of a trackway.

Something else is also interesting about the photograph above. You'll notice the moder tracks being left recently in the soft mud (upper left corner). Of course, these are never going to be preserved, because they will be weathered very soon. However, if they were old and if they had managed to get preserved how would you grade them? Can you recognise the track makers?

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)