7/20/17- cretaceous bone help- north tx

[John S.]

Found this chunk of a bone with matrix attached yesterday. This was lying in the creek next to Eagle Ford/Atco Formation. About 6 x 2 inches. First thought was Mosasaur jaw bone but it also looks fishy. Any thoughts? Thanks..

 

Far north central Texas 

upper cretaceous 

85-92 mya

...

[John S.]

Top

[RyanDye]

I found a pliosaur in the range of your described age. Perhaps the lower mandible that's my best guess. (Brachauchenius)

 

Pliosaurs' closest relatives are sharks so a fishy look could be present, not sure if they've ever been found in your form. I know they were around well in your age of the fossil hope this turns out useful.

[RyanDye]

Edit: I meant white sharks sorry. 

[John S.]

15 minutes ago, Ryan Dye said:

I found a pliosaur in the range of your described age. Perhaps the lower mandible that's my best guess. (Brachauchenius)

 

Pliosaurs' closest relatives are sharks so a fishy look could be present, not sure if they've ever been found in your form. I know they were around well in your age of the fossil hope this turns out useful.

Good call! It's possible, I did find a plesiosaur vertebra in same area a few years back. 

Plesiosaur skull:

[ynot]

I see no evidence of tooth sockets in this piece.

Looks more like a rib or long bone to Me.

Unfortunately there is not enough there to be sure about it.

Lable it "chunkasaurus".

Tony

 

PS white sharks did not appear until the miocene. And sharks do not have bones.

 

 

 

[RyanDye]

1 minute ago, ynot said:

I see no evidence of tooth sockets in this piece.

Looks more like a rib or long bone to Me.

Unfortunately there is not enough there to be sure about it.

Lable it "chunkasaurus".

Tony

 

PS white sharks did not appear until the miocene. And sharks do not have bones.

 

 

 

By closest living relative I was referring to the similar structure as I was not suggesting a phylogenetic relationship as that would be incredibly dubious I am not quite that incompetent... 

[Doctor Mud]

17 minutes ago, Ryan Dye said:

Pliosaurs' closest relatives are sharks 

 

Pliosaurs = Class Reptilia

Sharks = Class Chondrichthyes

 

A class is a huge group so sharks are fairly distant relatives to Pliosaurs.

 

 

 

 

[RyanDye]

2 minutes ago, ynot said:

I see no evidence of tooth sockets in this piece.

Looks more like a rib or long bone to Me.

Unfortunately there is not enough there to be sure about it.

Lable it "chunkasaurus".

Tony

 

PS white sharks did not appear until the miocene. And sharks do not have bones.

 

 

 

Look at the upper part of the jaw in John's reference the upper mandible is likely the area of the jaw which had no teeth.

[ynot]

2 minutes ago, Ryan Dye said:

By closest living relative I was referring to the similar structure as I was not suggesting a phylogenetic relationship as that would be incredibly dubious I am not quite that incompetent... 

Lizards are closer to plesiosaurs than sharks are.

Your statement makes no sense.

[RyanDye]

2 minutes ago, Doctor Mud said:

 

Pliosaurs = Class Reptilia

Sharks = Class Chondrichthyes

 

A class is a huge group so sharks are fairly distant relatives to Pliosaurs.

 

 

 

 

‘Jaws’ on a big scale

The New York Times reports there was another really, really big fish found in the northern Atlantic Ocean waters about 150 million years ago.

“They swam with mighty flippers, two fore and two hind, all four accelerating on attack,” wrote John Noble Wilford. “In their elongated heads were bone-crushing jaws more powerful than a Tyrannosaurus rex. They were the pliosaurs, heavyweight predators at the top of the food chain in ancient seas.”

Scientists have now literally uncovered fossils of a new pliosaur on Spitsbergen Island off Norway that is thought to be the largest marine reptile of its kind: “at least 50 feet long, 45 tons, with its massive skull 10 feet long, and the flippers, more like outsize paddles, also 10 feet. The creature — not yet given a scientific name but simply called the Monster or Predator X — hunted the seas 150 million years ago in the Jurassic Period.”

A two-hour documentary on the expedition to locate the fossils will be shown on the cable television History Channel at 8 p.m. March 29.

Scientists have assessed the skull remains and determined that the structure is “similar in many respects to the great white shark, the top predator in oceans today.” The critter “might have been comparable to the white shark in hunting strategy, but much more powerful.”

A Florida State University biologist ran some studies on the “bite force” of the pliosaur and came up with a 33,000-pound number, “more than 10 times that of any animal alive today and two to four times the bite force of T. rex. “There is nothing really comparable in the sea today,” the scientists concluded.

Let’s see — we’ve got something 50 feet long that has huge teeth, which can chomp on its prey with the force of more than 15 cars being dropped to the ground. Makes you glad you didn’t live 150 million years ago, eh?

 

 

As I said very clearly the "Closest living relative" I was refferring was not this:

 

 

 

 

I was referring more to convergent evolution since a pliosaur has no direct descendant with similar structure and size as pliosaurids died out of course true plesiosaurs have more relatives related them today such as what you described.  (I know very, very, well sharks ARE NOT RELATED TO PLIOSAURS GENETICALLY AT ALL) 

 

 

[Doctor Mud]

14 hours ago, John S. said:

Found this chunk of a bone with matrix attached yesterday. This was lying in the creek next to Eagle Ford/Atco Formation. About 6 x 2 inches. First thought was Mosasaur jaw bone but it also looks fishy. Any thoughts? Thanks..

 

Far north central Texas 

upper cretaceous 

85-92 mya

...

Love seeing your finds!

 

carefully cleaning out that matrix might help?

As @ynot was saying, unless you know the anatomy really well attributing some of these fragments to a specific group can be tough.

Bone structure can suggest a group e.g marine reptile in this instance, but may not be diagnostic beyond that.

 

I think @Ryan Dye meant bone structure might look similar to a bony fish - which confused us, but was on the right track in terms of bone structure as a useful indicator.

[RyanDye]

Just now, Doctor Mud said:

Love seeing your finds!

 

carefully cleaning out that matrix might help?

As @ynot was saying, unless you know the anatomy really well attributing some of these fragments to a specific group can be tough.

Bone structure can suggest a group e.g marine reptile in this instance, but may not be diagnostic beyond that.

 

I think @Ryan Dye meant bone structure might look similar to a bony fish - which confused us, but was on the right track in terms of bone structure as a useful indicator.

Yeah that's what I meant sorry I worded it strangely I can see the misconception.

[Doctor Mud]

Just now, Ryan Dye said:

Yeah that's what I meant sorry I worded it strangely I can see the misconception.

No problem!

Easy to do via the Internet 

Convergent evolution is fascinating.

 

[John S.]

Thanks for the insight guys I knew it was a long shot but it's great to hear from the experts

[JarrodB]

I'm seeing rib here.