bryozoan species Identification

[Denis Arcand]

I read some information somewhere suggesting that bryozoan species can be distinguished by the shape of their pores. Is it possible to identify the following bryozoan from this cross-sectional image? Additionally, could you provide insights into the criteria used for identifying bryozoan species? I have encountered limited online documentation on this topic and would appreciate any advice you can offer.

 

 

Edited December 28, 2023 by Denis Arcand

[ClearLake]

That is a nice looking specimen and I'm sure someone can ID it, but it is not me.  Bryozoan taxonomy is a whole other world, with lots of detail based on multiple thin sections.  If you would like to learn more, here is a good place to start:  https://www.bryozoa.net/orders.html  Go to the home page of this website to see what else they have to offer.  Be prepared to head down a deep deep rabbit hole!!  

 

I should note, that if one is familiar with the bryozoans of a particular formation, you often can ID then (at least partially) based on external characteristics, but that only works if you have a pretty limited list of options.

Edited December 28, 2023 by ClearLake

[Denis Arcand]

56 minutes ago, ClearLake said:

That is a nice looking specimen and I'm sure someone can ID it, but it is not me.  Bryozoan taxonomy is a whole other world, with lots of detail based on multiple thin sections.  If you would like to learn more, here is a good place to start:  https://www.bryozoa.net/orders.html  Go to the home page of this website to see what else they have to offer.  Be prepared to head down a deep deep rabbit hole!!  

 

I should note, that if one is familiar with the bryozoans of a particular formation, you often can ID then (at least partially) based on external characteristics, but that only works if you have a pretty limited list of options.

Thanks for the information and the link, I find the link very useful and the "GLOSSARY FOR BRYOZOA" they offer will help me narrow my search to find more information!!

 

I appreciate the warning about the deep rabbit hole - I'm always up for a good intellectual adventure.

If anyone else has information or experiences to share about bryozoans, I would love to know more. Thanks again for pointing me in the right direction.

Edited December 29, 2023 by Denis Arcand

[piranha]

Here is a list of Nicolet Fm. bryozoan genera compiled from Brandt-Velbel 1985 and Bretsky & Bretsky 1975.

 

I have no practical expertise except to confidently say it is not Prasopora!

 

Amplexopora
Batostoma
Bythopora
Coeloclema
Dekayia
Heterotrypa
Parvohallopora
Phylloporina
Prasopora
Stictopora

 

Brandt-Velbel, D. 1985
Stratigraphic Resolution in the Nicolet Formation (Upper Ordovician), Quebec, Canada.
PhD Thesis, Yale University, 378 pp.

 

Bretsky, P.W., Bretsky, S.S. 1975
Succession and Repetition of Late Ordovician Fossil Assemblages from the Nicolet River Valley, Quebec.

Paleobiology, 1(3):225-237

[BobWill]

In general they are some of the most difficult fossils to ID because of the small size and large variety of the details. Usually you have to make thin sections to see the different characters of the different features like acanthopores, mesopores and diaphragms. At least two are required, a longitudinal one parallel to the direction of growth and a tangential  one parallel to the surface and close enough to the surface to show the mature structure. You may need another tangential section just above the median lamia. Sometimes also a transverse section cut  at a right angle to the longitudinal for looking at median pores in the mesotheca of ramose forms. Did anyone mention all of the odd terminology you'll learn going down that rabbit hole?

[Denis Arcand]

23 hours ago, piranha said:

Here is a list of Nicolet Fm. bryozoan genera compiled from Brandt-Velbel 1985 and Bretsky & Bretsky 1975.

 

I have no practical expertise except to confidently say it is not Prasopora!

 

Amplexopora
Batostoma
Bythopora
Coeloclema
Dekayia
Heterotrypa
Parvohallopora
Phylloporina
Prasopora
Stictopora

 

Brandt-Velbel, D. 1985
Stratigraphic Resolution in the Nicolet Formation (Upper Ordovician), Quebec, Canada.
PhD Thesis, Yale University, 378 pp.

 

Bretsky, P.W., Bretsky, S.S. 1975
Succession and Repetition of Late Ordovician Fossil Assemblages from the Nicolet River Valley, Quebec.

Paleobiology, 1(3):225-237

 

Thanks for the list of “Nicolet Fm. bryozoan genera”, which may serve as a valuable starting point despite the anticipated challenges.

 

Thanks for the reference, I know it is on microfiche and can be viewed at “Library and Archives Canada” in Ottawa. I'm curious if there is another option to access it online? Accessing theses and other specialized documents has become increasingly difficult for me. In my youth, university libraries were open to everyone, but unfortunately this is no longer the case. Now access is restricted to students, making it more difficult for non-students like me to obtain the necessary materials.

 

 

[Denis Arcand]

23 hours ago, BobWill said:

In general they are some of the most difficult fossils to ID because of the small size and large variety of the details. Usually you have to make thin sections to see the different characters of the different features like acanthopores, mesopores and diaphragms. At least two are required, a longitudinal one parallel to the direction of growth and a tangential  one parallel to the surface and close enough to the surface to show the mature structure. You may need another tangential section just above the median lamia. Sometimes also a transverse section cut  at a right angle to the longitudinal for looking at median pores in the mesotheca of ramose forms. Did anyone mention all of the odd terminology you'll learn going down that rabbit hole?

 

Thanks for providing exactly the answer I was looking for regarding bryozoan identification. I really appreciate your expertise in untangling the complexities of this identification process.

Navigating the terminology associated with this subject is, indeed, akin to going down a rabbit hole. 🐇

[piranha]

2 hours ago, Denis Arcand said:

I know it is on microfiche and can be viewed at “Library and Archives Canada” in Ottawa. I'm curious if there is another option to access it online?

 

Accessing theses and other specialized documents has become increasingly difficult for me.

 

Check your PM for a nice surprise!