Jump to content

izak_

Mackunda Formation Early Cretaceous (Late Albian) Richmond, QLD, Australia

From the album:

Mackunda Formation

· 13 images
  • 13 images
  • 3 comments
  • 10 image comments

Photo Information


Recommended Comments

Jared C

Posted

Reminds me of Dwardius or Cardabiodon. I do not know anything about their specific occurences in Austrailia though

@Mikrogeophagus

  • I found this Informative 2
  • I Agree 1
Link to comment
Mikrogeophagus

Posted

Like @Jared C mentioned, I too think it looks like a Cardabiodontid (Dwardius and Cardabiodon). I'm not good at differentiating those, but I believe only Dwardius has been reported from rocks as old as the Albian. They are found in the Russian Albian under the name Dwardius siversoni. The article (https://dx.doi.org/10.1017/S0263593300002509) should cover the differences between the two genera, but I do not have access to it, so this is as far as I can go.

  • I found this Informative 2
  • I Agree 1
Link to comment
1 hour ago, Jared C said:

Reminds me of Dwardius or Cardabiodon. I do not know anything about their specific occurences in Austrailia though

@Mikrogeophagus

 

24 minutes ago, Mikrogeophagus said:

Like @Jared C mentioned, I too think it looks like a Cardabiodontid (Dwardius and Cardabiodon). I'm not good at differentiating those, but I believe only Dwardius has been reported from rocks as old as the Albian. They are found in the Russian Albian under the name Dwardius siversoni. The article (https://dx.doi.org/10.1017/S0263593300002509) should cover the differences between the two genera, but I do not have access to it, so this is as far as I can go.

 

Thank you both! These are some of the most common teeth in the area but I'm not sure if they're even described like with most of the Cretaceous sharks in Australia, I could be wrong though.

  • Enjoyed 2
Link to comment
ThePhysicist

Posted

Very nice tooth and photography! I agree with juvenile cardabiodontid, looks fairly convincing.

image.thumb.png.d15d9cd31c946822e7b625c44dbc9e98.png

http://oceansofkansas.com/sharks/Kansas/Cardabiodon/FairportCard02.jpg

 

On 7/7/2024 at 8:05 PM, Mikrogeophagus said:

The article (https://dx.doi.org/10.1017/S0263593300002509) should cover the differences between the two genera, but I do not have access to it, so this is as far as I can go.

Looks like it compares specific tooth positions. Also keep in mind this may not account for ontogeny. (lmk if you'd like the full paper.)

 

"Dental differences between Dwardius and Cardabiodon gen. nov. include: (1) the anterior teeth are markedly enlarged relative to the anteriorly situated lateroposterior teeth in Dwardius (see Woodward 1894, pi. 6, fig. 2), but not in Cardabiodon (Fig. 5); (2) the second to fourth upper anterior teeth have a markedly distally directed cusp in Cardabiodon. In Dwardius, anterior teeth appear to have a more or less straight cusp (see Woodward 1894, pi. 5, fig. 25a?, d, e, n?; pi. 6, fig. 2b?, d, f); (3) the teeth of the lateroposterior files in both the upper and lower jaws have a more distally directed cusp in Cardabiodon than in Dwardius; (4) distally situated lateroposterior teeth are more compressed labiolingually in Cardabiodon than they are in Dwardius, which has unusually stocky commissural teeth."

  • I found this Informative 3
Link to comment
1 hour ago, ThePhysicist said:

Very nice tooth and photography! I agree with juvenile cardabiodontid, looks fairly convincing.

image.thumb.png.d15d9cd31c946822e7b625c44dbc9e98.png

http://oceansofkansas.com/sharks/Kansas/Cardabiodon/FairportCard02.jpg

 

Looks like it compares specific tooth positions. Also keep in mind this may not account for ontogeny. (lmk if you'd like the full paper.)

 

"Dental differences between Dwardius and Cardabiodon gen. nov. include: (1) the anterior teeth are markedly enlarged relative to the anteriorly situated lateroposterior teeth in Dwardius (see Woodward 1894, pi. 6, fig. 2), but not in Cardabiodon (Fig. 5); (2) the second to fourth upper anterior teeth have a markedly distally directed cusp in Cardabiodon. In Dwardius, anterior teeth appear to have a more or less straight cusp (see Woodward 1894, pi. 5, fig. 25a?, d, e, n?; pi. 6, fig. 2b?, d, f); (3) the teeth of the lateroposterior files in both the upper and lower jaws have a more distally directed cusp in Cardabiodon than in Dwardius; (4) distally situated lateroposterior teeth are more compressed labiolingually in Cardabiodon than they are in Dwardius, which has unusually stocky commissural teeth."

 

Thank you very much, I appreciate it! A copy of the full paper would be great :) 

  • Enjoyed 1
Link to comment

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...