Croc Skull Or Fossil?

[AJ Plai]

My friend found this from the bottom of a river in Thailand and brought this to me

to see if its a skull from recently dead croc or is it a fossil. My gut feeling tells

me its a recently dead croc since it wasn't dug or excavated from a known fossil deposit

but I can't be sure; I have heard of people getting fossils from the bottom of the river

so it could be possible. Here are what it looks like:

It could be a current specie like the Crocodylus Siamensis, but I guess I will let someone

with more experienced with croc biology to be able to confirm that.

So what are the things that u can do to test to tell for certain if its a bone or a fossil?

Other than carbon-dating that is. Anyway thx for the help guys.

Edited February 24, 2013 by AJ Plai

[AJ Plai]

Here are some more pics of the skull:

[Scylla]

Well I for one would keep it either way. Does it feel mineralized? A hot needle may burn it if it is fresher bone. What is the geology around where it was found?

[RichW9090]

Can you tell me the length o the skulls? Measure from the tip of the nose to a line drawn between the two most rearward points on the skull. Easiest way is to back the skull up on a table top to the wall against which the table is pushed, and measure from the wall to the snout tip.

Rich

[RichW9090]

Your skull does not appear to be a Crocodylus siamensis, which has a smooth snout and a bony ridge behind each eye. The snout of C. siamensis is also relatively broader than in your specimen. I believe it to be a skull of Crocodylus porosus, the saltwater croc. Your skull has the typical two longitudinal ridges runing the length of the snout just to either side of the midline.

Salties occur today in Thailand.

If it is mineralized, it could be a fossil, although recent material in rivers can mineralize quite quickly - witness the well mineralized domestic pig material from Florida rivers. If it is not mineralized, it could be modern - although I have seen material 10,000 + years old that burns and smells like fresh bone.

Edited February 24, 2013 by RichW9090

[RichW9090]

Here is a nice site where, using the menu on the left side, you can flip from picture to picture of the head of modern crocodilians, all drawn to the same scale, in the same view:

http://crocodilian.com/cnhc/cst_cpor_am_head.htm

[AJ Plai]

The skull is about 47 cm long from what I have measured. I am not so

sure if the orange lines under the inside of skull's mouth could be

mineralization or just river dirt... When u say "mineralize feel", u

mean like agatization you see in some dino bones? Or it could be something

less showy or obvious?

At the moment, I am trying to get in touch with my friend who found

it to give more geology details but from what I know so far the area

this was found is under a river dirt and mud though the river is not known

to be a fossil site so I can't be sure.

Thx guys

Edited February 24, 2013 by AJ Plai

[AJ Plai]

I tried taking more close-up pics of the skull and inside details

of the skull, don't know if they will help much but here they are:

[mikeymig]

It looks like it has some age and if its not a fossil (10,000 years or older) its still a very cool specimen. How did your friend find it? Was he looking for river relics or is that something he just does, dig through the river bottom? If the river has saltwater crocs in it now and your friend is rootin around there has to be a good reason for it right?

mikey

[AJ Plai]

More pic of inside the croc skull:

MikeyMig

Yes, my friend was looking for river relics and found this by accident.

I would assume that the river is probably not populated by any big croc

nowadays or people probably wouldn't risk it, I think...

[RichW9090]

I have material in the collections here (a horse skull and a turtle skull) from a river in Thailand with the same sort of matrix encrustations and sediment staining on it.

[steelhead9]

I had a very similar croc skull found in a Thai river taken by US customs because importation of modern croc material is illegal under the cites treaty. I contacted them and argued that it was pleistocene and not a modern croc specimen. After nine months and, according to them, extensive testing, they agreed with me and returned the skull. I would think this a pretty good case for your skull being a fossil.

[Auspex]

...I would think this a pretty good case for your skull being a fossil.

I would certainly not rule it out based on a photograph.

[AJ Plai]

I have material in the collections here (a horse skull and a turtle skull) from a river in Thailand with the same sort of matrix encrustations and sediment staining on it.

Thx, very much for the info u provided That would seem like mine could be a genuine fossil - good news for me.

I had a very similar croc skull found in a Thai river taken by US customs because importation of modern croc material is illegal under the cites treaty. I contacted them and argued that it was pleistocene and not a modern croc specimen. After nine months and, according to them, extensive testing, they agreed with me and returned the skull. I would think this a pretty good case for your skull being a fossil.

Did you happen to find the croc skull in a river in Ang Thong province by any chance? This one was found in a river in Ang Thong province - a central region of Thailand. I was under the impression that, Thai fossils are only found in the sites in the North Eastern region which are known for containing some local species of dinosaurs and pre-historic elephants. Ang Thong or central region of Thailand, to my knowledge, doesn't seem to harbor any fossil-rich formations or sites, but I could be wrong. The area around the river is open plain, the riverbed has mixture of sand and clay - some bronze are known to be in the area also - don't know if these info are sufficient to be of any help.

Would love to see the pic of the croc skull if u still have it. It would probably help to be comparison materials with this one - if yours is fossil croc skull and it looks with condition just like mine then I guess mine has a very high chance of being a fossil, which will make this a pretty fantastic specimen!

Thx very much guys. Really appreciate the help.

*Note: I edited the location of the find in the post and added more details of the geography of the location after I re-checked with my friend*

Edited February 25, 2013 by AJ Plai

[jpc]

fossil or modern... it is very nice either way.

[AJ Plai]

fossil or modern... it is very nice either way.

It certainly is, I am considering trading for this skull with my Wii console + Games (which I hardly play anymore, LOL) that my friend has been wanting for a while ;p

Then I can get it mounted on a nice display, it will probably be the most complete large vertebrate specimen I have to date in my collection.

Edited February 25, 2013 by AJ Plai

[AJ Plai]

More geological information about the location found:

The area around the river where this skull was found is an open plain region (Ang Thong province), the riverbed has mixture of sand and clay - some bronze are known to be in the area also. From a little internet digging, some Pleistocene specimens have known to be found in this region, though I have yet to find anything mentioning about any Pleistocene croc yet.

Don't know if these info are sufficient to be of any help.

[mikeymig]

The more I look at it the older it gets.

[Ash]

AJ PAI: "Wow, I see some talk of Crocodylus Porosus, How did I miss this? Well, may be there are some croc experts here who could help me out - isn't Crocodylus Porosus a modern day specie also? So do the Pleistocene ones and the modern day ones any different in terms of features or biology and how could you tell?"

Yes, Crocodylus porosus is the modern day, and Pleistocene species. As best as i can tell there isnt any difference between the present day or Pleisto material in terms of features, size etc. As with most fossils, just because its a modern species certainly doesnt have to mean they are still in the area to have the remnants. Mine were found about 1800km from the nearest common occurance of them.

Any chance of a photo from directly above, and side on with it sitting teeth down? (No angles to the pictures?)

Cheers.

Ash

Will reply when i get home from work

[RichW9090]

From what I can see, it's pretty clearly C. porosus, as it has a leats the one apomorphy of the paired ridges down he length of the snout. It just a s clearly seems to lack the C. siamensis apomorphy of the ridge behind the eye. C. porosus is known as far back as the Pliocene in Australia, but I don't find any records in SE Asia - however, I would expect it to have occurred there also.

[AJ Plai]

AJ PAI: "Wow, I see some talk of Crocodylus Porosus, How did I miss this? Well, may be there are some croc experts here who could help me out - isn't Crocodylus Porosus a modern day specie also? So do the Pleistocene ones and the modern day ones any different in terms of features or biology and how could you tell?"

Yes, Crocodylus porosus is the modern day, and Pleistocene species. As best as i can tell there isnt any difference between the present day or Pleisto material in terms of features, size etc. As with most fossils, just because its a modern species certainly doesnt have to mean they are still in the area to have the remnants. Mine were found about 1800km from the nearest common occurance of them.

Any chance of a photo from directly above, and side on with it sitting teeth down? (No angles to the pictures?)

Cheers.

Ash

Will reply when i get home from work

Thx very much Ash, I will get some more pics from the angle u mention and upload it as soon as I get home also.

From what I can see, it's pretty clearly C. porosus, as it has a leats the one apomorphy of the paired ridges down he length of the snout. It just a s clearly seems to lack the C. siamensis apomorphy of the ridge behind the eye. C. porosus is known as far back as the Pliocene in Australia, but I don't find any records in SE Asia - however, I would expect it to have occurred there also.

The fossils that are known to have been found around the region where this croc skull was found are mammals like pre-historic wolf and buffalo from the Pleistocene, but like u said - no record of crocodile as far as I could find info. Though there was a discovery of a new pre-historic croc specimen like this one in Khorat region which has a rich fossil deposit:

There are however, stories of people finding fossils in rivers in Thailand but I guess since a lot of these aren't reported to geologist or paleontologist - so they go unrecorded and never really got studied to shine new light on other possible fossil deposits or sites other than the ones in North Eastern region.

[AJ Plai]

Ok, I dug out some more info and tried to do some geological research about the area where the skull was found, although I am absolutely clueless to the science of geology, but here goes:

According to this geological map:

http://www.thailand-smile.com/images/members/pierreto/Geological-Map-Of-Thailand.jpg

The region is where this was found is Quaternary with Fluvial deposits: flood plain, alluvium, terrace and colluvium.

Though, I have no idea what this geological info would tell or have any implication on this croc skull of mine. So, any paleontologist/geologist here that could help would be greatly appreciated. Thx!

[Ash]

I'm agreeing with Rich, C.porosus. Just had time to compare a couple pics with the ones you posted.

By any chance is being able to weigh them an indication as to mineralisation or not, guys/gals?

[RichW9090]

Weight, no. Density,yes. But remember, if your specimen is mineralized, it doesn't mean it is old - bones in river environments can mineralize very quickly.

Edited February 26, 2013 by RichW9090

[AJ Plai]

Ash

I have taken some more photos in angles as u asked:

Hope they are useful, Thx!