Help Id These Eagle Ford And Austin Group Boundry Finds. North Texas

[wfrr]

I have some Eagle Ford and Austin group boundry goodies that I hope a few of you might take a look at and tell me what you think.

Well heres a shark tooth different that any I've ever found. It's also the biggest I've ever found. Pretty cool. Maybe its a Cretoxyrhina mantelli. Maybe one of the experts would be kind enough to peg this one.

Here is something that looks like the floor from the lower jaw from a small mosasaur or some kind of fish. There are no teeth or anything else to help with ID. It's rather fragile. Even if I'm right about what it is I don't know what to call it. Your thoughts are appreciated.

This vert sure looks like a Mosasaur to me. Never found one this old before though what do you guys think?

Some shark teeth. I think the blunt ones are ptychodus. The bottom left is from the Ozan maybe squalicorax? I wish I had a pic of the killer ptychodus that my buddy found. It was huge about as broad width wise as a silver dollar. I'll try to get a pic to post. Hey...I got pics and I tried to put them up and somehow wound up with this picture section at the bottom, ck it out.

A lump of limestone with bones in it. My initial thought was bony fish. I don't see any verts in there.

A possible crab. You can imagine it better holding it in your hand.

A clam that maybe shouldn't have been where I found it, maybe it was washed down from some road gravel. I hoped to find more but bombed out.

The prevalent oyster I've been finding at this formation level. Some of them have the bottom on them it appears to be flat.

Edited May 14, 2013 by wfrr

[fossiladdict]

Looks like mosasaur verts to me, and your lump of limestone with bones it it look to be the ribs from the top part of the fish vert(s).

[Auspex]

The second item has all the earmarks of being a "Tilly" bone: a hyperostotic fish bone.

[Foshunter]

Last three pix looks to be Pytodus mortoni, hard to ID with the icing on top----Tom

Edited March 11, 2013 by Foshunter

[RichW9090]

I think the Tilly bone is specifically one of the dorsal or anal fin spines. Tilly bones can be vertebrae, spines or the tail fan bone.

[vertman]

Hey!

I will take a shot at helping with some IDs. Did all of these come from the same location? That is sort of a wierd assemblage of fossils coming from the same place. It looks to me like various zones and maybe even formations are exposed.

I agree with your ID on the first shark tooth being a partial, Cretoxyrhina mantelli.

I guess the vert must be a mosasaur vert, the only other creature posessing a large vert like that during that timeframe being a plesiosaur. That does not look like a plesiosaur vert to me.

In the image with multiple shark teeth, you definitely have a couple of Ptychodus. I can't really tell exactly what species given their size in the image. The lower of the two may be P. anonymous. I really can't see the other one well enough to venture a guess. A couple of the teeth on the right side of that image look like Scapanarhynchus texanus. The one you indicated from the Ozan may not be Squalicorax as it looks like it has a partial side cusp preserved? If it does have the side cusp it may be a Cretolamna instead.

The lump of limestone with bones is definitely part of a fish.

I don't see a crab in that one piece and I am not sure about the white clam in the other.

The oysters in the group are a very distinctive fossil. They are a pretty good index fossil for a very specific layer within the Arcadia Park formation. I have almost always found one or two lenses of shark teeth in association with these oysters. If you find these oysters in situ, look 4-5 feet above them and I bet you see a layer with a lot of small and mostly broken Scapanarhynchus teeth. The genus and species of this oyster escapes my memory right now.

The very large tooth does look like a Ptychodus mortoni. I am going mostly by the x-shaped ridge at the tip of the tooth. This tooth looks like it came from the base of the Austin Group (Basal Atco) in very far north Texas. It does not look like it came from the same layer as the others, that is why I asked the earlier question.

Nice grouping of fossils, by the way.

[Boneman007]

Nice stuff! Congrats!

[Jesta384]

Could a light vinegar bath clean up that Ptychodus mortoni a little better? It certainly looks like a nice specimen, lines and all.

[Boneman007]

Vinegar will turn shark teeth white. Avoid at all costs.

[wfrr]

I'll respond to the question vertman asked in the post so it can be as informative as possible for any future reference.

The fossils indeed all came from the same waterway in North Texas with the exception of the clam and possible crab which were both found at another nearby area just upstream from the Kamp Ranch. One of the teeth as mentioned was collected from the Ozan.

I agree with vertman...some of the teeth we picked up in the arcadia park looks very much like what was later found by us upstream at the basal atco zone.

All of it was discovered maybe 1 1/2 to 3 miles downstream from the basal atco. This was before I discovered the basal atco zone. These finds prompted me to try and figure out where they were coming from. Now that I know the likely answer I imagine they washed downstream just like the oysters must have.

It is amazing how difficult this grouping of fossils were to find given the large area searched. Most people wouldn't bother with it. In fact most of my fossil hunting buddys don't want to go to the arcadia park-upper britton areas anymore.

I am certain that we miss most of the shark teeth in the creek bed. There has to be more. Indeed even at the basal atco formation none of us have picked up a single tooth out of the creek bed. All of them have been found in situ in the fish zone.

I also suspect that there are more zones in the upper arcadia park as suggested by vertman and perhaps on into the upper britton. If anyone wants to take a stab at identification for the oyster marker fossils I'd sure appreciate it.

[DPS Ammonite]

Your oysters, if they came from the uppermost Eagle Ford Fm., are Cameleolopha bellaplicata. BTW, I have found the smaller Cameleolopha lugubris mentioned in the paper below in the Atco member of the Austin Chalk at the TXI quarry in Midlothian, TX. See paper titled:

"The Late Cretaceous oyster Cameleolopha bellaplicata (Shumard 1860), guide fossil to middle Turonian strata in New Mexico"

by Hook.

[wfrr]

That is excellent thanks for your help!

[CStewart]

Your oysters, if they came from the uppermost Eagle Ford Fm., are Cameleolopha bellaplicata. BTW, I have found the smaller Cameleolopha lugubris mentioned in the paper below in the Atco member of the Austin Chalk at the TXI quarry in Midlothian, TX. See paper titled:

"The Late Cretaceous oyster Cameleolopha bellaplicata (Shumard 1860), guide fossil to middle Turonian strata in New Mexico"

by Hook.

I've also found similar ones in the same area. These are neat.

[wfrr]

Thats it. I have a site with a very nice lens of those with a few other things mixed in here and there.

[CStewart]

Cool, check out this big boy! Found in the same creek

[Diceros]

Most of the IDs in this old (2013) thread are correct, and require no comment. A few, however, do.

The bone here called a Tilly bone appears instead to just be a flattened, large marine bony fish pterygiophore - it doesn't appear to be at all hyperostotic, as all Tilly bones are.

The mosasur bones appear to be post. caudal vertebrae of a small mosasaurine, like Clidastes. Turonian mosasaurs like this are some of the oldest mosasaurs known from America.

In the shark & ray tooth pic, the sm. Ptychodus pavement teeth look like P. whipplei, the common lt. Turonian species. There appear to be three partial teeth of the goblin shark Scapanorhynchus r. raphiodon (later replaced by S. r. texanus). There's a partial up. lat. tooth of Cretolamna appendiculata in the lw. left.

A comment should be made about the difference between the clam and the oyster shell. Oyster, scallop, and jingle shells are made of calcite, and are more stable than most clam shells, which is why the oyster shells themselves have been preserved. The clam is a phosphatic steinkern (internal mold - a form characteristic of transgressive lags), whose shell has been completely dissolved. The clam shell was originally made of the less stable mineral aragonite, and has completely dissolved. Because of the acidic groundwater that often preferentially flows through the coarse clastics of transgressive marine lags, all aragonitic shells are usually dissolved in them.

[wfrr]

Nice ...thanks for your input I appreciate it.

[sixgill pete]

Vinegar will turn shark teeth white. Avoid at all costs.

I use vinegar often to break down limestone matrix among others. Never has turned my teeth white. If you leave the matrix soaking to long it can break down the roots. I usually soak for 24 hours, drain off the vinegar and wash well with cold clear water until all traces of the vinegar is gone. I occasionally soak single teeth in it that have matrix attached. Again, never seen one turn white. With single teeth I soak 12 hours or so and wash well. The matrix softens sometimes and then can be carefully removed.

[wfrr]

I use vinegar frequently to clean, break down matrix..etc... and so far I've experienced no problems of any kind.