Mazon Creek Seed Or Creature (Arthropod?)

[Stocksdale]

Here's a mystery item. When I first looked at this, the curve and dimensionality of it made me think it was a seed (trigonocarpus). However, looking at it closer, it looks much more like animal than plant. Maybe not arthropleura, but perhaps some other creature?

Overall shape sort of suggests a segmented arthropod.

Here is detail of the 'pointed' end. Notice the pattern of raised lines running along it.

Here area details of the rounder end.

EDIT: This was found near Coal City around the border between Braidwood and Essex.

Edited November 19, 2013 by Neophytus Elginian

[Auspex]

The hallmark of the images of arthropleura material that I have seen is a 'bumpy' texture, rather than ridged. This is not to say that this is not arthropleura, or some other arthropod, only that it is not what I expect to see for them.

I'd like to know what it is!

[Stocksdale]

And while I'm posting. Here are two others that are unknown and (to my novice eyes) suggested something like segments of an animal but might be some plant material.

Other item 1:

Other item 2: (front and back).

[Rob Russell]

The first fossil posted looks "cone-ish" to me?

[Stocksdale]

In real life, it looks less cone-ish and more like a slice of an orange. That is what originally pointed me toward seed.

It had some similarities to some examples of triginocarpus or Rhabdocarpus. I think they divide into three slices/segments. The one posted below (from Sam Noble Museum in Oklahoma) has ridges but they aren't quite like the ones on mine.

Edited November 20, 2013 by Neophytus Elginian