(Another) unknown invertebrate

[Mainefossils]

This is yet another invertebrate fossil that has perplexed me. In the field I thought it was an ostracod, but under closer inspection it has shown itself to be something different. I don't think that it is a brachiopod piece this time, but bryozoan would possibly fit. Another possibility I thought of was the end of an extremely small trilobite glabella, with a dent running through the center. Yet another possibility is nothing, but it is pretty symmetrical, so I think it is a fossil.  

 

I presume it is from the Hersey Formation. I found it on the seashore, and it seemed to be brought by the current. There are ostracods in it that match with what I know of this formation, but I am uncertain. All the formations in the area, though, are Silurian. 

 

It is approximately 900 microns long. 

 

Here are pictures of it: 

 

 

[Rockwood]

The mold left of center ?

Looks like a small spirifer.

[Mainefossils]

@Rockwood

Thanks for the suggestion! I thought that Spiriferids began in the Ordovician, and that would rule them out, but if some species did exist in the Silurian, I would be glad to hear about them. Thanks for your time! 

[Rockwood]

1 hour ago, Mainefossils said:

@Rockwood

Thanks for the suggestion! I thought that Spiriferids began in the Ordovician, and that would rule them out, but if some species did exist in the Silurian, I would be glad to hear about them. Thanks for your time! 

?

Cambrian, Ordovician, Silurian. Isn't that how it goes paleontologist style ? From the bottom up.

[EMP]

On 6/13/2021 at 7:40 PM, Mainefossils said:

This is yet another invertebrate fossil that has perplexed me. In the field I thought it was an ostracod, but under closer inspection it has shown itself to be something different. I don't think that it is a brachiopod piece this time, but bryozoan would possibly fit. Another possibility I thought of was the end of an extremely small trilobite glabella, with a dent running through the center. Yet another possibility is nothing, but it is pretty symmetrical, so I think it is a fossil.  

 

I presume it is from the Hersey Formation. I found it on the seashore, and it seemed to be brought by the current. There are ostracods in it that match with what I know of this formation, but I am uncertain. All the formations in the area, though, are Silurian. 

 

It is approximately 900 microns long. 

 

Here are pictures of it: 

 

 

 

Kind of hard to tell what you're talking about. The big lump kind of in the middle? Maybe an ostracode? 

 

2 hours ago, Mainefossils said:

@Rockwood

Thanks for the suggestion! I thought that Spiriferids began in the Ordovician, and that would rule them out, but if some species did exist in the Silurian, I would be glad to hear about them. Thanks for your time! 

 

Spiriferida began in the late Ordovician, yes, and they existed until the Jurassic. There are several Silurian spiriferid species, but they're different from their Devonian relatives and not as common. Eospirifer is perhaps the best known genus I can think of. 

[Mainefossils]

@Rockwood

Thanks for the pointer! Sorry, I made a silly mistake.  I accidentally switched the entire thing around! So a Spiriferid could work for this one.

 

@EMP

Thanks for the info. An ostracod is another possibility that I will have to look into more. The "fossil" is the large lump in the middle.

 

Thanks for your time everyone! 

[Fossildude19]

It may just have to end up being a mystery item. 

I am having a hard time seeing any kind of detail that would lead to a confident ID.   

[Rockwood]

52 minutes ago, Mainefossils said:

The "fossil" is the large lump in the middle.

In that case a simple no should suffice.