Possible new undescribed arthropod? House range Utah

[Al Tahan]

Hey everyone, 

 

I just got back from an amazing trip to Utah and Nevada collecting a host of trilobites. I am going to try and post some photos of that trip in the next day or so. I never seem to be able to find the time anymore! This find was pretty much the trip maker for non trilobite finds. 
 

I found this soft tissue arthropod in the house range in rocks known to have Burgess Shale fauna. So far this doesn’t seem to line up with anything I’ve seen in the Burgess. I’ve had 2 suggestions on an identification. Canadaspis perfecta is the best guess so far however there are glaring differences. The similarities to Canadaspis would have me thinking this could still be related (family or genus level?) as it shares the same body plan but with different proportions. The other suggestion was Eldonia but I’m far more skeptical of that. 
 

to me this is clearly some type of arthropod with a distinct head, carapace, body segments and legs. If it has a name I don’t seem to have the reach in my research tools to figure it out. The gut tract is also preserved in this specimen too. This has been confirmed by reputable sources so that also makes this even more wild of a specimen. If this turns out to be something unknown to science that would sure be a surprise....we seem to have slapped names on almost everything at this point lol.  
 

here is a photo of the slightly more detailed side.

 

Here is a little diagram showing anatomy. 
 

searching desperately for my scale bar (eye roll emoji lol).....one I find a good scale I’ll put up another photograph. It’s only about an inch or prolly 3-4cm tip to tip in a straight line not measuring the curve of the animal. 
 

 

If anyone with Burgess Shale knowledge or some deep pocket knowledge on Cambrian arthropods want take a guess, let me know what you think! 
 

Al
 

 

[Top Trilo]

Wow that is a fantastic specimen! not sure what it is though

[Fossildude19]

Great find, Al!   

 

Have a look at this website.

Mollisonia symmetrica Walcott 1912  looks slightly similar.   

 

We need an expert on this -  @piranha

[Fossildude19]

Cropped, enlarged, and brightened:

 

      

[sharkdoctor]

@Al Tahan That's a really intriguing find! Would love to see your other goodies from the trip when you find the time.

[dinosaur man]

Interesting not sure what it is

[RCFossils]

Interesting specimen 

I am leaning towards Eldonia.

I have a similar looking example from the Wheeler Shale.

[Huntonia]

Fantastic specimen! I also feel a bit more inclined towards Eldonia. 

[piranha]

5 hours ago, Fossildude19 said:

Have a look at this website.

Mollisonia symmetrica Walcott 1912  looks slightly similar. 

 

Congrats on the find @Al Tahan Great minds think alike @Fossildude19---Bruce Lieberman has replied:

 

Thanks very much for sending the picture.  I do know what it is and in fact it is quite significant because it is something that is pretty rare: it’s Mollisonia and it’s also a very nice one.  So, awesome find!  I should say by the way that if this specimen was something that you were ever interested in depositing in a museum we would definitely be very excited if you were interested in depositing it here.  However, if not of course I’d understand and no worries.  In any event, thanks again for sharing, and really a great discovery.

 

***Al: Please send me a PM if you want to donate this important specimen.

[Tidgy's Dad]

Nice find.

What a beautiful fossil. 

[FossilNerd]

Great find Al! Congrats! 

[Reebs]

Congratulations on your find!! Super cool!! 

[piranha]

I have heard back from a couple of other Cambrian arthropod specialists. They are of the opinion it is either a hurdiid radiodont appendage or a bivalved arthropod.

Please attempt to take additional well-focused photos of the part and counterpart.  Ideally: a halogen light source at an angle above that shows maximum details.

 

Thanks! 

 

[Wrangellian]

Wow... you lucky bum! Everywhere you go you're finding great stuff!  I went to southeastern B.C. last year for trilobites etc and didn't find anything that I would call a tripmaker (though I thought I had but it turned out to be nothing special). I guess Utah and Nevada are the places to go.

My first thought on this was partial radiodont mouth but let's see what the experts have to say.

[Top Trilo]

2 minutes ago, Wrangellian said:

Wow... you lucky bum! Everywhere you go you're finding great stuff!

I know, just a month ago he got those amazing pyritized triarthrus trilobites back!

[Wrangellian]

Indeed!

[Al Tahan]

Ok finally got a chance to check back in here and read all this. Very exciting stuff here! I’ve been in the bivalved arthropod camp since I found it but I’m in no way 100% convinced. I’ll take some more photos tonight and put them here. I would consider donating it at some point if it’s really something unknown. 
 

@sharkdoctor I plan on hopefully doing it tomorrow night. Lots of photos! 

[Nautiloid]

Awesome find Al!! 

[Sjfriend]

Great find Al. 

[Al Tahan]

Here is my best try at more clear photos. Just doesn’t seem to want to cooperate. Usually I lose resolution When I post pictures. If need be I can email photos to @piranha and he can send it to the correct scholars. 
 

I realize even these aren’t so good. Maybe I’ll try to put up higher resolution photos of the ones I already posted 

[Al Tahan]

 

here’s another attempt at a higher resolution photo. I’m trying it as high resolution as I can while zooming in 

 

 

 

[Al Tahan]

This counterpart won’t cooperate as much with the picture and light but I hope this still proves better.