Possible Worm?

[sarahjane]

This image is of what I believe may be a worm. I added arrows along the main section of the fossil and one where the fossil reemerges from the matrix (top arrow). There is also a close up - this section is where the middle arrow is in the first picture - and shows both the external and internal structures. Hopefully helpful for ID. It was found in a brickyard in Mississauga Ontario. I can't figure out what it might be other than a worm, but I can't find anything similar to it yet. Any help would be greatly appreciated

[mommabetts]

Do you know the age of the formation it was found in? Knowing that would help to narrow it down.

[mommabetts]

Oh and welcome to the forum.

[sarahjane]

Hi,

as it happens I can be very specific because of where I find all my fossils. I have pasted information from the Ontario Government Geological Survey because I figure it's better to give too much info than not enough but don't feel compelled to read it - the upshot is that my general area is Ordovician, sedimentary rocks deposited in shallow inland seas. The specific location (Canada Brick, Streetsville) is a known outcrop of the Queenston formation (easily weathered, maroon-coloured shale with interbeds of grey-green shale, limestone and siltstone). Hope that helps!

"BEDROCK GEOLOGY

With the exception of a small area of the Precambrian Canadian Shield in the extreme northeastern corner of the District, Southwestern Ontario is underlain by sedimentary rocks of Paleozoic Age. (350 – 500my)

All rock units are flat-lying and undeformed with a gentle regional dip to the southwest. The sedimentary rocks that comprise the Paleozoic succession were largely deposited in shallow marine environments, at times when the area was covered by a series of inland seas.

Rocks on the southeast edge of the District were influenced by sedimentation in the foreland Appalachian Basin. Rocks in the northwest portion of the District form a major portion of the east-side of the Michigan Basin. The Algonquin Arch, a broad basement ridge, dissects the District in a southwest orientation separating the two basins. The basins and arch controlled the distribution and accumulation of sediments. The thickness of Paleozoic strata over the Precambrian basement increases in a southwesterly direction from zero to a maximum of 1350 m near Sarnia. Paleozoic rocks are, from west to east, Devonian, Silurian and Ordovician in age.

Ordovician

Precambrian gniess and felsic igneous rocks of the Grenville Province are overlain by Ordovician age rocks. The Shadow Lake Formation consists of red and green, dolomitic and sandy shale, generally 2 to 3 m in thickness, unconformably resting on Precambrian basement. The overlying succession of limestones, carbonate mudstones, calcareous shales and non-calcareous shales of the Gull River, Bobcaygeon, Verulum and Lindsay Formations represent relatively continuous deposition. These units comprise the Simcoe Group.

The Simcoe Group is overlain by sediments of the Blue Mountain, Georgian Bay and Queenston Formations. The Blue Mountain Formation is a blue-grey-brown, non-calcareous shale. The Georgian Bay Formation, which underlies much of Toronto, is a blue-grey shale with minor siltstone and limestone. The Queenston Formation is an easily weathered, maroon-coloured shale with interbeds of grey-green shale, limestone and siltstone. It forms the base the Niagara Escarpment. The Niagara Escarpment is a prominent erosional cuesta, with an east-facing scarp, which bisects the District in a southeast orientation.

[Guest solius symbiosus]

It is a crinoid stem. The other fossils with the small tubular patterns are bryozoans.

Here are couple that I found in Kentucky. They are of the same age as the formations you listed. At the top of the picture, you can see where the stem attaches to the calyx on the one to the left.

[Guest Nicholas]

It is a crinoid stem. The other fossils with the small tubular patterns are bryozoans.

Here are couple that I found in Kentucky. They are of the same age as the formations you listed. At the top of the picture, you can see where the stem attaches to the calyx on the one to the left.

I Agree entirely.

[sarahjane]

It is a crinoid stem. The other fossils with the small tubular patterns are bryozoans.

Hi,

The bryozoans I know, but I didn't think it was a crinoid because it doesn't look like any I recognize and there are tons around where I found this and I have several different specimens and it looks nothing like any of those. Also, although it's hard to see in the photos, it isn't tubular, it has sharp corners- almost square - and there is what looks like a seam running the length of the exterior which I didn't think crinoids had. I wish I could describe it better (or had a macro lens - a pox on my telephoto SLR) but with the line it looks like ab muscles (600 pack?) or a zipper. Any idea what would cause that and what kind of crinoid you think it might be?

Thanks to both of you for the quick responses

[Guest solius symbiosus]

It is virtually impossible to id a crinoid by the stem alone. Yours has weathered down nearly to the cavity that housed the nerve structure in the center of "stalk". The lines that you are seeing are the sutures between the individual ossicles.

If you look at the stem part on the pic that I posted, you can see what appear to be "squared" sides. In reality, it is pentagonal.

Traces of worms are found in Ordovicion rocks. Usually as burrows, but their mouth parts(Scolecodont) are fairly common. They are very small and usually require a microscope to be seen.

Here is one collected from Ordovicion rocks of Kentucky.

Arabellites sp.

[Fred]

Definitely crinoid. It seems that some weathering of the fossil took place, exposing the interior 'channel' of the stem. The weathering also explains the sharp corners you're talking about.

[Auspex]

I don't disagree with crinoid stem; I think the "worminess" is an artifact of weathering and/or deformation.

I am curious about the "feathery" object next to it; here's a crop:

[Guest solius symbiosus]

^^It is a trepostomate bryozoa that has weathered/fractured along the sagittal axis.

[Major]

Check this out, if you're still unsure:

http://tolweb.org/Crinoidea