Asialepidotus Fish Fossil

[Crazyhen]

This fish fossil is said to be an Asialepidotus from Liaoning, China. It is pretty well preserved.  I wonder if it is a genuine one.  It is 30cm in size for the fish. 

[oilshale]

There is something completely wrong with this slab. Asialepidotus shingiensis is from the Triassic of Yunnan and Guizhou - the small fish is a Lycoptera from the Cretaceous of Liaoning.  The 'Asialepidotus' looks quite strange - if I remember well, this fish does not have such a long dorsal fin. It might be a composite. It might be an  to be inlay  or glued on top of a slab from Liaoning.

Thomas

[RJB]

The color of the matrix the fish is in is completely different in color to the surrounding matrix.  Something very fishy about this slab.  Pun intended. 

 

RB

[oilshale]

1 hour ago, RJB said:

The color of the matrix the fish is in is completely different in color to the surrounding matrix.  Something very fishy about this slab.  Pun intended. 

 

RB

Agreed, the matrix from Xingyi and Luoping is dark grey to black, but can be also dark brown - the matrix from Liaoning is more brownish. This fish is definitely not an Asialepidotus (Eugnathus, Sinoeugnathus) shingyiensis - looks more like a (cast or genuine) Robustichthys luopingensis  inlay in a Liaoning slab.

 

I would tend to an inlay made with an original slab from Liaoning and a cast from (may be) Robustichthys. I am not sure, but these small dark spots could be air bubbles. This would proof it is an inlay.

 

 

 

This is an Asialepidotus from Xingyi, Guizhou

[Crazyhen]

Perhaps it was misidentified by the seller as Asialepidotus.  I agree that it looks more like Robustichthys luopingensis.  Regarding the difference in colour in the matrices, could it be due to different colour of the layers of matrix?   The specimen was collected from Lingyuan, Liaoning.

[oilshale]

3 hours ago, Crazyhen said:

Perhaps it was misidentified by the seller as Asialepidotus.  I agree that it looks more like Robustichthys luopingensis.  Regarding the difference in colour in the matrices, could it be due to different colour of the layers of matrix?   The specimen was collected from Lingyuan, Liaoning.

Agreed, the difference in color can be due to a different color of the deeper layer. The color difference does not worry me so much - this can be natural.

What worries me more is the rather antiquated look of this fish. This fish is clearly a Holostei, a fish with rather thick ganoid scales and primitive characteristics. The Triassic was the prime time for Holostei. Already in the Jurassic , Holostei fish got rare and in the Cretaceus, the Teleostei (fish with much thinner scales and better maneuverability) took almost completely over. As far as I know, the only Holostei which can be found in the Cretaceus of Liaoning is Sinamia zdanskyi. But this fish looks completely different, like an Amis or Cyclurus (dogfish). 

Thomas

[Crazyhen]

The fish specimen was said to be from the Triassic, but I am not sure if it is correct or not, so as the locality.  However, does it look like a genuine fossil?  And I note with particular interest the rather round tail of the fish.

[oilshale]

The Triassic fish appears to be genuine, but to be sure, it would be necessary to have a closer look at it.

The other fish on the lower right is for sure a (genuine) Lycoptera davidi from the Early Cretaceous of Liaoning.

 

Decorative piece and good work of a forger, but not the right thing for a serious fossil collection.

Thomas

 

PS: These "fantasy combinations" are not so uncommon - I once saw a Cretaceous turtle combined with a (Devonian?) trilobite. This is a "Jurassic Park" slab - extinct species of different geologic age living together in the present time.

 

[Crazyhen]

4 minutes ago, oilshale said:

The Triassic fish appears to be genuine, but to be sure, it would be necessary to have a closer look at it.

The other fish on the lower right is for sure a (genuine) Lycoptera davidi from the Early Cretaceous of Liaoning.

 

Decorative piece and good work of a forger, but not the right thing for a serious fossil collection.

Thomas

 

PS: These "fantasy combinations" are not so uncommon - I once saw a Cretaceous turtle combined with a (Devonian?) trilobite. This is a "Jurassic Park" slab - extinct species of different geologic age living together in the present time.

 

So, you mean this slab is likely to be an inlay of a Triassic fish in a matrix with a Cretaceous fish?  I couldn't understand why they put such an effort making something like this.  The Triassic fish, in its original slab, would be a nice fossil itself alone.

[oilshale]

52 minutes ago, Crazyhen said:

So, you mean this slab is likely to be an inlay of a Triassic fish in a matrix with a Cretaceous fish?  I couldn't understand why they put such an effort making something like this.  The Triassic fish, in its original slab, would be a nice fossil itself alone.

I fully agree, I would be more interested in the Triassic fish alone. May be the slab was just not big enough to make a nice display piece.

 

I also use this technique from time to time:

The stone slab of this little shark didn't look good - it was just too small and not very attractive.
That's why I took another slab from Solnhofen and fitted the shark in.

 

[Crazyhen]

I have double checked with the seller.  He insisted that no inlay was done and the slab was collected from Liaoning, and both the big fish and the small fish are found in the same slab.  That's interesting if what he said is true, the big fish with its more elongated dorsal find and round tail fin, does not look like Robustichthys or Asialepidotus.

[oilshale]

I think I have finally identified this Holostei - it seems to be Sinamia liaoningensis. This fish was described in 2012 by Jiang-Yong Zhang. Amia (Bowfin) and the Lepisosteiformes (Gars) are the only surviving recent members of the Holostei.

Thomas

A NEW SPECIES OF SINAMIA FROM WESTERN LIAONING CHINA.pdf

[Seguidora-de-Isis]

One Sinamia liaoningensis here makes perfect sense, and I think it really is. I must admit that the fossil of this seller is infinitely more beautiful than the holotype itself that was used to describe this species:

 

 

It is not so common for Liaoning standards, quite the contrary, it is rare, but there really may be different shades of the layers of matrix. All I care about is the great difference in color shades between Lycoptera davidi and the supposed Sinamia liaoningensis. The two fossils should have the same hue, as in the overwhelming majority of cases. So only this detail got a little suspicious for me.

 

Nevertheless, the Asialepidotus shigyiensis is from the Guizhou Province, that is, from the Middle Triassic Period, between 270 and 210 million years ago, while the Liaoning Province is from the Cretaceous Period, Barremian Stage, between 130 and 125 Million years.

 

But an Asialepidotus shigyiensis I can guarantee it really is not. Below, I leave as an example, a legitimate specimen of Asialepidotus shigyiensis that is deposited in my private collection;