Opalised Dinosaur Tooth Fossil

[Alston Gee]

I recently acquired this opalized fossil from Lightning Ridge, Australia. The seller told me it was an opalized pine cone stem fossil, while some of my friends argued that it might be a tooth fossil. I noticed that this opalized fossil shares some similarities with an ankylosaur tooth. Could it be possible that this fossil is actually an opalized ankylosaur tooth?

[Kohler Palaeontology]

I believe ankylosaurs are present in Australia, I have only heard of scutes being found from them in Lightning Ridge, so it's plausible. So far, I am not seeing any bone texture, so I don't think it's a bone, I can't help if it's a pine fossil or an Ankylosaur tooth.

 

Here are some ankylosaurid teeth from Victoria, Australia [1].

 

References:

1. Barrett, P., Rich, T., Rich, P. V., Tumanova, T., Inglis, M., Pickering, D., Kool, L., & Kear, B. (2010). Ankylosaurian dinosaur remains from the Lower Cretaceous of southeastern Australia. Alcheringa, 34(3), 205 - 217. https://doi.org/10.1080/03115511003655430

Edited Thursday at 10:18 AM by Kohler Palaeontology

[Kohler Palaeontology]

If it is a tooth, it could also be an ornithopod tooth.

Edited Thursday at 08:04 AM by Kohler Palaeontology

[Mahnmut]

Hi,

I see the resemblance.

Close inspection of the serrated part may help.

Gastropod columnella is another possible id in my eyes, especially if the serrations turn out to be irregular breaks.

Best regards.

J

[Fossildude19]

I didn't think enamel could turn to opal.

I think this is more likely pine cone or gastropod.  Not enough left to say for sure, in my opinion. 

For me, I would label it pretty rock. 

[Kohler Palaeontology]

Teeth can be opalized. 

[Kohler Palaeontology]

Here is a beautiful image of one. Don't know the paper it's from. It's a megaraptorid tooth

 

And this one. 

Edited Thursday at 10:49 AM by Kohler Palaeontology

[Mahnmut]

26 minutes ago, Fossildude19 said:

I didn't think enamel could turn to opal.

I think it can.

https://www.facebook.com/SedaOpals1/videos/shark-teeth-opalized-these-are-very-rare-as-the-ridge-area-used-to-be-fresh-wate/329338691046434/

https://undark.org/2019/07/24/chasing-opal-fossils-australian-outback/

Still not sure about this specimen.

Best regards,

J

[jpc]

how big is this specimen.  That will be an important clue. 

And I htink it is fair to say that we will need much better photos. The last two are from a good angle, but all I see is an out of focus something.

[Alston Gee]

51 minutes ago, jpc said:

how big is this specimen.  That will be an important clue. 

And I htink it is fair to say that we will need much better photos. The last two are from a good angle, but all I see is an out of focus something.

The length of the fossil is 2.5 cm. I will try to take a clearer photo once I receive the fossil.

Edited Thursday at 05:36 PM by Alston Gee

[jpc]

2.5 cm = 1 inch... too big to be an ankylosaur tooth. 

[Alston Gee]

54 minutes ago, jpc said:

2.5 cm = 1 inch... too big to be an ankylosaur tooth. 

The top part of the fossil (“the tooth crown”) seems to be slightly less than 1 cm, while the bottom part (“the tooth root”) is 1.5+ cm.

[Alston Gee]

3 hours ago, jpc said:

2.5 cm = 1 inch... too big to be an ankylosaur tooth. 

I am confused about the ‘opening’ structure at the base of the fossil, which helps me distinguish this fossil from bones and gastropods. I have seen several opalized tooth fossils from Australia that exhibit similar features, such as a hollow tooth root filled with mud. I have also not seen any pine stem fossils with this unique feature. If this fossil is not an ankylosaur tooth, could it possibly be an ornithosaur tooth? Is Nodosaur a possible candidate?

Edited Thursday at 09:53 PM by Alston Gee

[Kohler Palaeontology]

Here are some ornithopod teeth from Australia (some are from Lightning Ridge). I have provided these for help to ID this tooth. These are only ornithopod teeth, not ankylosaur.

 

FIG. 1 [1]

Isolated ornithopod teeth from the Griman Creek Formation. (A, C and E-G) Photographs and (B and D) interpretive illustrations of a complete dentary tooth (LRF 492) in (A and lingual, (C and D) labial, (E) mesial, (F) distal, and (G) apical views. (H) Cross-section of the root taken at the level indicated by the dashed line in (B). (I and K) Photographs and (J and L) interpretive illustrations of a nearly complete maxillary tooth (QM F14421; cast of AM F119236) in (I and J) lingual and (K and L) labial views. (M) Close up of secondary ridges denoted by boxed region in (J). (N and P) Photographs and (O and Q) interpretive illustrations of worn dentary tooth (AM F119236; i.e. QM F14420, cast) in (N and O) lingual and (P and Q) labial views. (R and T) Photographs and (S and U) interpretive illustrations of premaxillary tooth (LRF 660; cast) coated in ammonium chloride (for clarity) in (R and S) labial and (T and U) lingual views. (V and X) Photographs and (W and Y) interpretive illustrations of dentary tooth (AM F112862) in (V and W) lingual and (X and Y) labial views. (Z and BB) Photographs and (AA and CC) interpretive illustrations of dentary tooth (AM F112862) in (Z and AA) lingual and (BB and CC) labial views. Dark grey in (B) and (D) indicates broken surfaces. Cross hatching in (U) indicates area obscured by archiving label. Abbreviations: art, casting artefact; for, foramen; fu, furrow on secondary ridge; pr, primary ridge; ling, lingual; wf, wear facet. Photo and illustration credit: Phil Bell. Full-size  DOI: 10.7717/peerj.6008/fig-6

 

(I seriously don't know why there is a face with sunglasses on there, I did not put it there.)

 

FIG. 2 [1]

Figure 4 Weewarrasaurus pobeni gen. et sp. nov.(LRF 766). Right dentary in (A) medial, (B) lateral, and (C) dorsal views. Three-dimensional render of the erupted crown and root in (D) mesial, (E) lingual, (F), distal.

 

FIG. 3 [3]

Figure 2 Ornithopod dental terminology. Abbreviations: Cin, cingulum; Cra, central root axis; Dbr, distal bounding ridge; Dcl, denticle; Dr, distal secondary ridge; Mbr, mesial bounding ridge; Mr, mesial secondary ridge.

 

FIG. 4

Figure 3 Weewarrasaurus pobeni gen. et sp. nov. (LRF 3067; holotype). Right dentary in (A), medial; (B), dorsal; and (C) lateral views. Dashed black lines represent approximate contours of the missing areas. Dashed red.

 

 

Refferences:

S1,2,3,4 FIG. Bell PR, Herne MC, Brougham T, Smith ET. 2018. Ornithopod diversity in the Griman Creek Formation (Cenomanian), New South Wales, Australia. PeerJ 6:e6008 https://doi.org/10.7717/peerj.6008

[Alston Gee]

1 minute ago, Kohler Palaeontology said:

Here are some ornithopod teeth from Australia (some are from Lightning Ridge). I have provided these for help to ID this tooth. These are only ornithopod teeth, not ankylosaur.

 

FIG. 1 [1]

Isolated ornithopod teeth from the Griman Creek Formation. (A, C and E-G) Photographs and (B and D) interpretive illustrations of a complete dentary tooth (LRF 492) in (A and lingual, (C and D) labial, (E) mesial, (F) distal, and (G) apical views. (H) Cross-section of the root taken at the level indicated by the dashed line in (B). (I and K) Photographs and (J and L) interpretive illustrations of a nearly complete maxillary tooth (QM F14421; cast of AM F119236) in (I and J) lingual and (K and L) labial views. (M) Close up of secondary ridges denoted by boxed region in (J). (N and P) Photographs and (O and Q) interpretive illustrations of worn dentary tooth (AM F119236; i.e. QM F14420, cast) in (N and O) lingual and (P and Q) labial views. (R and T) Photographs and (S and U) interpretive illustrations of premaxillary tooth (LRF 660; cast) coated in ammonium chloride (for clarity) in (R and S) labial and (T and U) lingual views. (V and X) Photographs and (W and Y) interpretive illustrations of dentary tooth (AM F112862) in (V and W) lingual and (X and Y) labial views. (Z and BB) Photographs and (AA and CC) interpretive illustrations of dentary tooth (AM F112862) in (Z and AA) lingual and (BB and CC) labial views. Dark grey in (B) and (D) indicates broken surfaces. Cross hatching in (U) indicates area obscured by archiving label. Abbreviations: art, casting artefact; for, foramen; fu, furrow on secondary ridge; pr, primary ridge; ling, lingual; wf, wear facet. Photo and illustration credit: Phil Bell. Full-size  DOI: 10.7717/peerj.6008/fig-6

 

(I seriously don't know why there is a face with sunglasses on there, I did not put it there.)

 

FIG. 2 [1]

Figure 4 Weewarrasaurus pobeni gen. et sp. nov.(LRF 766). Right dentary in (A) medial, (B) lateral, and (C) dorsal views. Three-dimensional render of the erupted crown and root in (D) mesial, (E) lingual, (F), distal.

 

FIG. 3 [3]

Figure 2 Ornithopod dental terminology. Abbreviations: Cin, cingulum; Cra, central root axis; Dbr, distal bounding ridge; Dcl, denticle; Dr, distal secondary ridge; Mbr, mesial bounding ridge; Mr, mesial secondary ridge.

 

FIG. 4

Figure 3 Weewarrasaurus pobeni gen. et sp. nov. (LRF 3067; holotype). Right dentary in (A), medial; (B), dorsal; and (C) lateral views. Dashed black lines represent approximate contours of the missing areas. Dashed red.

 

 

Refferences:

S1,2,3,4 FIG. Bell PR, Herne MC, Brougham T, Smith ET. 2018. Ornithopod diversity in the Griman Creek Formation (Cenomanian), New South Wales, Australia. PeerJ 6:e6008 https://doi.org/10.7717/peerj.6008

Thanks for sharing this informative reference! I have doubts about whether the piece I own could be classified as a Nodosaur, as Nodosaur teeth are generally larger and have similar roots to those of Ankylosaurs. I am still confused, and it seems that no one can clearly identify it.

[Alston Gee]

@Paleoworld-101

[Kohler Palaeontology]

I could be wrong, but I am pretty sure that all ankylosaurids from Australia are nodosaurs, and most of them are pretty small.

[Alston Gee]

On 8/21/2015 at 4:27 PM, Ridgehiker said:

Curious. What are these types of teeth? Never sure if Ankylosaur or Pachycephalosaur. I find all types of variations of these teeth in various formations from 65 to 75 million years of age. Length 2cm with root.

 

7 minutes ago, Kohler Palaeontology said:

I could be wrong, but I am pretty sure that all ankylosaurids from Australia are nodosaurs, and most of them are pretty small.

I believe you are certainly right! I’m not sure about the general size of an Australian Nodosaur tooth, but judging by the size of an Ankylosaur tooth from a previous post, it seems that Ankylosaurs do have teeth around 2 cm in length or even longer. If you think this opalized fossil is not a good candidate for an Ankylosaur, what do you think it could be? A gastropod, a pine stem, or something else? 

[Kohler Palaeontology]

I don't know much about Lightning Ridge material, so unfortunately, I can't help much. My biggest interest is actually the dinosaurs of Alberta, Canada. You could always message the Australian Opal Center; they would probably know.

 

But I would recommend watching this video, it goes over identifying Lightning Ridge material, they have other videos that also might help. 

 

[Paleoworld-101]

Could be a tooth but i am leaning towards a suggestively shaped bit of opal due to the lack of identifiable apicobasal ridges. Unfortunately with opal fossils there is no internal structure to confirm something as bone or tooth so all we have to rely on is external morphology, and in this case it is ambiguous.

 

13 hours ago, Kohler Palaeontology said:

I could be wrong, but I am pretty sure that all ankylosaurids from Australia are nodosaurs, and most of them are pretty small.

 

Recent papers place Kunbarrasaurus in the clade Parankylosauria which is a group of basal ankylosaurians that are neither nodosaurids nor ankylosaurids. Minmi on the other hand has been recovered as the basalmost taxon within Ankylosauridae by a couple studies, but its position within Ankylosauria is still ambiguous. I don't think any nodosaurid material is known from Australia.