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Upper Mississippian Bryozoan? Or Worm Tubes?


Archimedes

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I have found these alot at certain localities and this one of the best specimen I have seen,

it looks alot like Hederella chesterensis discribed by Bassler,

but it look alot like worm tubes too

post-385-0-15208900-1364759646_thumb.jpg

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sounds good, I have never seen worm tubes that branch then branch again like this

Yes I seen the little "Spirorbis" sp. but they have been remove from the genus by Taylor

Thanks Indy

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Although it is apparent it has been classified as a bryozoan, i have been looking at them with a microscope, the 9-10 specimens I collected last week in various weathered states, and i see nothing that would lead me to believe it to be a bryozoan. Indy pointed out the "Spirorbis" in the pic and the bryozoan (Hederella) have a very similar shell under the microscope so I have to lean towards Indy’s view of it being a worm tubes?? but i have never looked at worm tubes or bryozoans much

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Bryoazans are known to build some very interesting shapes.
This subject brings to mind the Mississippian bryozoan Evactinopora
Click Here
Note: All pictures are clickable to view magnified images


Click on Morphology
The individual bryozoan animals, the zooids, are found on
the faces of the rays or blades.

Flash from the Past (Show Us Your Fossils)
MAPS Fossil Show

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Hederella is a well studied bryozoan. I have several species from the Devonian of New York State. There are many forms that bryozoa can take. This is definitely different than most but not uncommon in the right rocks.

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I think this is Hederella but Hederella is no longer considered a bryozoan. Here are a couple of links: http://users.physics.harvard.edu/~wilson/arsenic/conferences/2007_GSA/AM/P123339.htm

and in the middle of this blog there is a discussion of them (a very interesting blog by the way) :http://woostergeologists.scotblogs.wooster.edu/2013/02/

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I think this is Hederella but Hederella is no longer considered a bryozoan. Here are a couple of links: http://users.physics.harvard.edu/~wilson/arsenic/conferences/2007_GSA/AM/P123339.htm

and in the middle of this blog there is a discussion of them (a very interesting blog by the way) :http://woostergeologists.scotblogs.wooster.edu/2013/02/

Good detective work but Hederella is still being described as a bryozoan since they published the follow-up paper to the GSA abstract. The blog is compelling although this caveat leaves plenty of wiggle room by saying: "Their shell microstructure and budding patterns suggests instead that they may be related to the phoronids...". Here is a LINK to a 2011 GSA abstract that still has Hederella classified as cyclostomate bryozoan. There are also a handful of peer-reviewed papers between 2010-2013 that still regard Hederella as a bryozoan. Either a bunch of folks didn't get the memo or we need to see a more convincing argument.

image.png.a84de26dad44fb03836a743755df237c.png

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Here's a link to Paul Taylor's publications : https://www.etis.ee/portaal/isikuCV.aspx?PersonVID=68146〈=en

He studies and publishes on bryozoans and in his 2010 paper titled "Evolution and Biomineralization in 'Lophophorates'" he discusses the reasoning why Hederelloids probably aren't bryozoans. This publication is about a third down on his list of publications.

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Here's a link to Paul Taylor's publications : https://www.etis.ee/portaal/isikuCV.aspx?PersonVID=68146〈=en

He studies and publishes on bryozoans and in his 2010 paper titled "Evolution and Biomineralization in 'Lophophorates'" he discusses the reasoning why Hederelloids probably aren't bryozoans. This publication is about a third down on his list of publications.

Yes, I'm well aware that Paul Taylor is one of the top bryozoan specialists. The point I was making is no one else has followed with a peer-reviewed paper that corroborates Hederella is not a bryozoan. Further, the recent evidence cited is compromised because the surface patterns of hederelloids and phoronids compared are opposing surfaces (concave & convex). I'm fairly certain, like you, that he is probably correct but evidently that still requires additional proof.

In the paper you cited Taylor et al. states:

"A robust phylogeny is still pending for lophotrochozoan phyla, including lophophorates, but should eventually come from combined molecular and morphological data. Until lophotrochozoan phylogeny is better resolved, any conclusions regarding the evolution of biomineralization in lophophorates must be viewed as highly tentative. Not withstanding this strong caveat, we propose a model that maps the fossil history of lophophorates and inferred lophophorates onto a phylogenetic framework derived largely from molecular studies."

image.png.a84de26dad44fb03836a743755df237c.png

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Thank You All, interesting discussion, we see the relationships of Hederella being questioned

Thanks for the info, it is a great help

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I think it is a coral.

"Absence of evidence is not evidence of absence"_ Carl Sagen

No trees were killed in this posting......however, many innocent electrons were diverted from where they originally intended to go.

" I think, therefore I collect fossils." _ Me

"When you have eliminated the impossible, whatever remains, however improbable, must be the truth."__S. Holmes

"can't we all just get along?" Jack Nicholson from Mars Attacks

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