Large Triassic fish from Sydney

[izak_]

A large fish from the Ashfield Shale SW of Sydney, Australia. The nodule it's in is really annoying to work with, it fractures vertically in most cases so lots of smaller pieces are missing. Unfortunately the specimen is pretty poorly preserved so I labelled one of the photos with what some parts may be, please feel free to correct me if any labels are incorrect. Also, it is difficult to photograph the details well due to poor contrast between the fossil and matrix, so hopefully these photos are adequate (I may readjust some soon).

 

Thank you for any help!

 

Skull 

 

Pectoral fin?

 

Caudal fin

 

Pelvic fin?

 

Dorsal fin?

 

Possible fin from the lower middle part of the body

Edited July 8, 2023 by izak_

[patelinho7]

I want to say I see a coelacanthid-looking tail which means it would be a Diplurus, maybe a Diplurus Newarkii or Longicaudatus. I could be wrong, though. I’ve just started learning Triassic fauna. The best person to ask would be @Fossildude19 when he is able.

[Fossildude19]

Pretty sure it's not a Diplurus.   Diplurus newarki is only found in the north east of the USA, and is quite small, comparatively speaking.  Maximum length is 8 inches or so.

Diplurus longicaudatus is a larger coelacanth, but only found in the Newark Supergroup, as far as I know.

Not sure there is enough visible/well enough preserved to be able to identify it further via pictures.   

[RJB]

Very interesting.

 

RB

[rodrex]

based on the diamond shaped scales I would suggest either Elonichthys armatus or palaeonensicis 

 

[Littleforest]

Very well spotted. How did you find this in a built up area like Ashfield?

[izak_]

On 7/8/2023 at 10:19 PM, patelinho7 said:

I want to say I see a coelacanthid-looking tail which means it would be a Diplurus, maybe a Diplurus Newarkii or Longicaudatus. I could be wrong, though. I’ve just started learning Triassic fauna. The best person to ask would be @Fossildude19 when he is able.

 

On 7/8/2023 at 10:25 PM, Fossildude19 said:

Pretty sure it's not a Diplurus.   Diplurus newarki is only found in the north east of the USA, and is quite small, comparatively speaking.  Maximum length is 8 inches or so.

Diplurus longicaudatus is a larger coelacanth, but only found in the Newark Supergroup, as far as I know.

Not sure there is enough visible/well enough preserved to be able to identify it further via pictures.   

 

On 7/15/2023 at 10:25 PM, rodrex said:

based on the diamond shaped scales I would suggest either Elonichthys armatus or palaeonensicis 

 

Thank you all for your help!

 

On 7/15/2023 at 10:41 PM, Littleforest said:

Very well spotted. How did you find this in a built up area like Ashfield?

The Ashfield Shale extends all the way down to the Southern Highlands, there are lots of road cuttings south and west of Sydney with exposed material  

[Littleforest]

2 minutes ago, izak_ said:

 

 

Thank you all for your help!

 

The Ashfield Shale extends all the way down to the Southern Highlands, there are lots of road cuttings south and west of Sydney with exposed material  

 

ah.. thank you for educating me. Similar to the Sydney Basin being greater than Sydney.

 

by the way, would you mind taking a look at the fossil ID I posted a few days ago? I’ve not had any responses so far.