New member with a jellyfish?

[dwillingman]

Has anyone ever heard of someone finding a solicified jellyfish fossil with a bunch of babies in The Matrix with the adult?

[A.C.]

Jellyfish fossils do exist (I have a Mazon creek one) though even one I know is a jellyfish I struggle to see it. 
 

It’s very uncommon in the fossil record to have jellyfish, though not unheard of. 
 

If you could post clearer pictures and or post geologic information that may help some members more experienced give you a positive ID on this.

 

Welcome to the forum!

[Meganeura]

5 minutes ago, A.C. said:

Jellyfish fossils do exist (I have a Mazon creek one) though even one I know is a jellyfish I struggle to see it. 
 

It’s very uncommon in the fossil record to have jellyfish, though not unheard of. 
 

If you could post clearer pictures and or post geologic information that may help some members more experienced give you a positive ID on this.

 

Welcome to the forum!

You need to get an octomedusa jelly from MC - theyre much more visibly jellies than Essexella are! 

[dwillingman]

7 minutes ago, A.C. said:

Jellyfish fossils do exist (I have a Mazon creek one) though even one I know is a jellyfish I struggle to see it. 
 

It’s very uncommon in the fossil record to have jellyfish, though not unheard of. 
 

If you could post clearer pictures and or post geologic information that may help some members more experienced give you a positive ID on this.

 

Welcome to the forum!

I know that's what I've heard they are very rare. What got me about this one is if you look very closely in that Matrix on one side there's at least 15 babies and on the other side there's probably twice that many as well as complete if not partials of three to four other adults I can't find on the internet and we have a huge rock shop here in town I live in Austin these ladies I've known them for 25 years have never seen something like this by kind of the Cornerstone of my collection now and now that I figured out what they look like I've run across the site where I'm finding lots of jelly

[JohnJ]

Welcome, Don.  These are not jellyfish.  Based on your photos and profile location, you likely have a piece of limestone full of rudists.  

 

LINK

[dwillingman]

I found this fossil in north west Austinnear FM 620 & Anderson Mill Rd

 In a clients yard where some cave entrances had been filled in. The way they would do that is dig around the openings and just dump it Down in the Hole. Sometimes rocks like this would fall out of the bucket

[Ludwigia]

I agree with JohnJ. No jelly here.

[JohnJ]

5 hours ago, dwillingman said:

I found this fossil in north west Austinnear FM 620 & Anderson Mill Rd

 In a clients yard where some cave entrances had been filled in. The way they would do that is dig around the openings and just dump it Down in the Hole. Sometimes rocks like this would fall out of the bucket

 

That places it right in the rudist filled Edwards Limestone.

[dwillingman]

[dwillingman]

I do understand that this was not near any of those formations though this was around a cave or two or three caves they're right there in that area I just downloaded or uploaded some more pictures in those pictures you get a more clear view of I think they're called the tendrils coming off the bottom of the jellyfish and if you looked in the holes in the rock especially I think in the last picture you can see those fine little hair like tendrils coming down through the holes this is not a hard shelled conical bivalve

[dwillingman]

There are no cliffs in that area it's a residential subdivision flat about three or four cave entrances were covered up in that subdivision. The small ones that are also on or in that Matrix look classic jellyfish not conical. I'm not trying to be argumentative as soon as I saw it I knew what it was and as soon as my friends who have owned the largest fossil and rock shop in Austin Texas in Central Texas or I don't know 25 30 years at least knew exactly what it was as soon as they saw it I'm not seeing a conical Bible when I see it I'm seeing the the Dome part of the jellyfish and then the tendrils coming off the bottom of it wrapping down through that rock and then I'm seeing the baby jellyfish that look like classic little jellyfish don't look conical they're just you know that top rounded part and then the little tendril is coming off the bottom

[Tidgy's Dad]

The photos are not very clear, but it is certainly not a jellyfish. 

Rudist is a possibility. 

[dwillingman]

17 hours ago, JohnJ said:

Welcome, Don.  These are not jellyfish.  Based on your photos and profile location, you likely have a piece of limestone full of rudists.  

 

LINK

 I posted some new pictures I think you can get a better look now this is clearly not a conical hard shelled bivalve. In these pictures you can more clearly see the tendrils coming off the bottom of the jellyfish you can see more clearly the Dome the cap I guess of the jellyfish and if you look in the holes down beneath it especially I think in the last picture you can very clearly see the fine hair like tendrils of the jellyfish all of the babies are not conical in shape they are domed with little things coming off the bottom

[Tidgy's Dad]

I think you are seeing what you wish to see. It's an example of pareidolia, quite natural and normal. 

This is clearly not a fossil jellyfish, but does appear to be a fossil of some hard shelled kind. 

[JohnJ]

5 hours ago, dwillingman said:

There are no cliffs in that area it's a residential subdivision flat about three or four cave entrances were covered up in that subdivision. The small ones that are also on or in that Matrix look classic jellyfish not conical. I'm not trying to be argumentative as soon as I saw it I knew what it was and as soon as my friends who have owned the largest fossil and rock shop in Austin Texas in Central Texas or I don't know 25 30 years at least knew exactly what it was as soon as they saw it I'm not seeing a conical Bible when I see it I'm seeing the the Dome part of the jellyfish and then the tendrils coming off the bottom of it wrapping down through that rock and then I'm seeing the baby jellyfish that look like classic little jellyfish don't look conical they're just you know that top rounded part and then the little tendril is coming off the bottom

 

 

Don, I have merged the new topic and photos you posted with this one.  Please add any new photos in a Reply to this topic.  Multiple topics about the same piece cause confusion and duplication of effort.

 

The cliffs (geography) in the link I posted are not important to the bedrock geology.  The area you described is in the Edwards Limestone formation.  The rocks from that formation are known for the abundance of caprinid rudist fossils.  The ones you pictured above are a different type rudist much younger in age.

 

Since these rudists formed reefs, chunks of the reef will show groups of them in bizarre angles of cross section.  Experienced collectors in Central Texas have seen countless numbers of them.  In some areas, their body cavities are often lined with beautiful, small crystals.  

 

Lots of fossils and rocks look like things they are Not.  Identification depends on more than a general appearance.  

 

Try taking your photos outside in natural light.

[dwillingman]

Okay thank you I appreciate that

[dwillingman]

Rudists don't have dangling tendrils do in the picture just before the modern era jellyfish you can see a dark spot a hole in the Rock and if you zoom in on that you can see what I'm talking about and in the picture I think above that you can see the tendrils very clearly they're very distinct outfit from The Rock I'm just I'm having a hard time wrapping my mind around that because rudists dint have tendriks do they?

[Fossildude19]

3 minutes ago, dwillingman said:

Rudists don't have dangling tendrils do in the picture just before the modern era jellyfish you can see a dark spot a hole in the Rock and if you zoom in on that you can see what I'm talking about and in the picture I think above that you can see the tendrils very clearly they're very distinct outfit from The Rock I'm just I'm having a hard time wrapping my mind around that because rudists dint have tendriks do they?

 

That is your mistake. They aren't tendrils. No, ... rudists did not have tendrils, but I don't see tendrils in your items, either.

I see what may be roots, or calcitic crystal growth, but not tendrils.

 

You need to understand that it takes a very certain set of circumstances for soft tissue to fossilize. Rapid burial, anoxic mud,  little to no bioturbation or scavenging, and the right types of minerals percolating through the rock as it is forming. All in all, quite rare. And even then, soft tissue is not preserved in 3-D, but usually as flattened, carbonaceous films.

 

If you don't believe us, please take your items to a local museum or college/university, and have a paleontologist look at them.

 

[JohnJ]

3 hours ago, dwillingman said:

Rudists don't have dangling tendrils do in the picture just before the modern era jellyfish you can see a dark spot a hole in the Rock and if you zoom in on that you can see what I'm talking about and in the picture I think above that you can see the tendrils very clearly they're very distinct outfit from The Rock I'm just I'm having a hard time wrapping my mind around that because rudists dint have tendriks do they?

 

Please try get better focused photos in natural light.

 

What you are seeing as "tendrils" are likely remains of the tubelike structures in the walls of their shells.  Check out these links to get a grasp of how this weird bivalve shows up in solid rock.

 

Link

 

Link

 

LINK

 

@JamieLynn

[JamieLynn]

Those are some really cool rudists there! And yes, as everyone has said, while they very much DO look like jellyfish, they are not. The limestone matrix here in Central Texas does not preserve jellyfish, nor any other thing that is softbodied. Only things with shells or tough exteriors like echinoids and ammonites and such make it through the fossilization process in this environment. 

Rudists are a weird bivalve that have a shell very much like an oyster, so what you are seeing as tendrils are the growth lines on the shell of the rudist. Similar to this one. While is is obviously not exactly like yours, you can at least start to recognize the outer shell structure and those growth lines. Now these are not in the limestone matrix, so it will look different than if squashed in the limestone matrix

 

Here is another Rudist that can be deceptive looking...all those radiating linear parts are just part of the shell structure:

 

And this one, if you didn't know it was a rudist, you might think it was a variety of things.

]

 

I hope this helps...Nature loves to trick us by making things that look like things which turns out are not the things we think they are! hahahha! I once found what I SWEAR was a giant crab claw, but alas,....it was just a cool limestone weathered rock.