Probably an easy one. Two (or one: see post) fossil animals from Neuville Fmt., Trenton Group (Neuville, Québec Province, Canada)

[alpha8768]

Hey there, me again (since my first ever post had great success)!

 

The photos I am about to show you may depict one or two different animals, found in the Neuville Formation of the Trenton Group (Middle Ordovician). The host rock would be micritic limestone and all pictures were taken in Neuville, 30 km west of Quebec City (Québec Province, Canada). Stratas had a subhorizontal dip, slowly sinking into the Saint Lawrence River.

 

Today, I have 6  pictures showing 6 different specimens. The photos might be showing the same animal, but seen from the top AND the bottom (which are quite different). In my opinion, those are probably encrusting bryozoans. The first three pictures would be the top of the animals, with the individual zooeciums (hundreds of small zooid holes) still preserved; whereas the last three ones would show the bottom. The thing is: I'm not sure and I never asked anyone knowledgeable.

 

My second guess would imply two different animals. The three first pictures would show the top of encrusting bryozoans (or something else?), while the last three ones would be another animal (algae? stromatoliths? sponges?). I'm open to your feelings and diagnosis.

 

Thank you very much!

 

 

[Kane]

The first one is definitely a bryozoan. Your photos are making me miss my time out in the Neuville! I've encountered the ringed fossil a few times but never paid them much attention in my pursuit for trilobites and echinoderms. 

 

I think the Neuville is placed in the upper Ordovician, though, equivalent to the Lindsay/Cobourg of Ontario. The profusion of Flexis and Ceraurus seem to suggest that. If you haven't been, there's a great abandoned quarry in L'ange Gardien area that also has a lot of Cryptolithus, too. 

 

PS: if you find anything really unique, you might want to get in touch with Mario at the Musée de paléontologie et de l'évolution (MPE) in Montrėal. He has a fantastic repository of Quebec fossils, probably the best in the world. I still have stuff to donate to him. 

[Fossildude19]

Picture 4 looks like the base of a rugose coral, to me. 

[Kane]

2 minutes ago, Fossildude19 said:

Picture 4 looks like the base of a rugose coral, to me. 

That's the weird thing about the Neuville: an absence of coral, for whatever paleoecological reasons. I wouldn't rule out brach for the ringed specimen, along the lines of Schizotreta. 

[Kane]

In terms of sponges, here is one I found in the Neuville (still needs to get into Mario's hands). One other has been found by a collector there. These are quite rare and significant, so definitely don't toss these aside!

[Northern Sharks]

The ringed fossil looks like the underside of a Prasopora bryozoan. We used to find plenty in the Lake Simcoe area here in Ontario. The small pieces in your first pics are bryozoans too, and possibly small Prasopora, but the only way to be sure is by thin sectioning them and looking under a microscope. I used to love seeing the small ones like that because, here anyway, there were often edrioasteroids nearby.

[alpha8768]

2 hours ago, Kane said:

The first one is definitely a bryozoan. Your photos are making me miss my time out in the Neuville! I've encountered the ringed fossil a few times but never paid them much attention in my pursuit for trilobites and echinoderms. 

 

I think the Neuville is placed in the upper Ordovician, though, equivalent to the Lindsay/Cobourg of Ontario. The profusion of Flexis and Ceraurus seem to suggest that. If you haven't been, there's a great abandoned quarry in L'ange Gardien area that also has a lot of Cryptolithus, too. 

 

PS: if you find anything really unique, you might want to get in touch with Mario at the Musée de paléontologie et de l'évolution (MPE) in Montrėal. He has a fantastic repository of Quebec fossils, probably the best in the world. I still have stuff to donate to him. 

 

Wandering in Neuville Fmt is like wandering in your old favorite childhood RPG game: even though it feels just like home, you always find something new  As for its age, I had the same hesitation as you, but the Quebec Geological Survey (Géologie Québec) puts it Middle Ordovician: Neuville Formation (gouv.qc.ca) .

 

WHERE is that quarry in l'Ange-Gardien (coordinates or Google Maps)? :O I used to live in Boischatel right next to this area, which I still sometimes explore while nordic skiing or by mountain bike when I visit my parents!

 

2 hours ago, Kane said:

That's the weird thing about the Neuville: an absence of coral, for whatever paleoecological reasons. I wouldn't rule out brach for the ringed specimen, along the lines of Schizotreta. 

 

Exactly: I've never found any corals in Neuville Fmt. Corals weren't that widespread in Mid Ordovician, but you can still find some in similar strata elsewhere... A mystery.

 

2 hours ago, Kane said:

In terms of sponges, here is one I found in the Neuville (still needs to get into Mario's hands). One other has been found by a collector there. These are quite rare and significant, so definitely don't toss these aside!

 

Very impressive finding. The best I've seen for Neuville.

 

1 hour ago, Northern Sharks said:

The ringed fossil looks like the underside of a Prasopora bryozoan. We used to find plenty in the Lake Simcoe area here in Ontario. The small pieces in your first pics are bryozoans too, and possibly small Prasopora, but the only way to be sure is by thin sectioning them and looking under a microscope. I used to love seeing the small ones like that because, here anyway, there were often edrioasteroids nearby.

 

Exactly what I thought. The idea came from an illustration I've seen during my degree, showing both sides of an encrusting bryozoan. Very similar! 

[Kane]

8 minutes ago, alpha8768 said:

 

Wandering in Neuville Fmt is like wandering in your old favorite childhood RPG game: even though it feels just like home, you always find something new  As for its age, I had the same hesitation as you, but the Quebec Geological Survey (Géologie Québec) puts it Middle Ordovician: Neuville Formation (gouv.qc.ca) .

 

WHERE is that quarry in l'Ange-Gardien (coordinates or Google Maps)? :O I used to live in Boischatel right next to this area, which I still sometimes explore while nordic skiing or by mountain bike when I visit my parents!

 

 

Exactly: I've never found any corals in Neuville Fmt. Corals weren't that widespread in Mid Ordovician, but you can still find some in similar strata elsewhere... A mystery.

 

 

Very impressive finding. The best I've seen for Neuville.

 

 

Exactly what I thought. The idea came from an illustration I've seen during my degree, showing both sides of an encrusting bryozoan. Very similar! 

Quebec stratigraphy is a hot mess.  

I will tell you the location over PM about that quarry. Many good Ceraurus were found there. 

[Ludwigia]

I agree with Prasopora. Here is a typical sample of the same age as yours from Gamebridge, Ontario with a ø of 7cm.