Gastropod or ammonite?

[Kohler Palaeontology]

Hello forum,

 

This was my first trilobite I ever found, a couple of years ago now, I've found so, so many since. It's quite unique as I've never seen trilobites this HUGE from this site, they're usually, I'd say maybe one third the size, and are usually orange in colour, very strange.  And not only that, but there also appears to be a gastropod next to it, which aren't the most common from the site to my knowledge either.

 

Probably a silly question, but I am not sure if this is a gastropod or an ammonite, I am not too familiar with invertebrates. I don't know if ammonites are found at the site or not. But it is mid-eastern NSW. Not extremely far from the coast. I believe it is carboniferous; I'm almost 100% sure but could be wrong. But I believe some other members on the forum have gone there and could help me out. I don't need to know the species or genus, but if anyone knows what species or genus this is, feel free to let me know, although it may be a little worn to tell.

 

I am not willing to share site information like locations. 

 

Here are the photos:

 

 

Don't know what this is, just noticed it today when taking these photos. Sorry for the blurry photo, I mainly wanted to know if the gastropod was an ammonite or gastropod. 

 

Top view with ruler. You can see all 3 fossils. Again, I am mainly asking about the gastropod.

 

Kind Regards,

Kohler Paleontology

 

 

 

[Ludwigia]

 Although it's missing a lot of substance, I can still see that the spiral appears to be 3-dimensional, so I would go with gastropod, although I'm not absolutely sure about that just going by these photos. Ammonoids generally have a flat spiral. By the way, true ammonites in the strict sense didn't appear in the geological record until the late Triassic. Carboniferous ammonoids are mostly goniatites.

[Kohler Palaeontology]

13 hours ago, Ludwigia said:

 Although it's missing a lot of substance, I can still see that the spiral appears to be 3-dimensional, so I would go with gastropod, although I'm not absolutely sure about that just going by these photos. Ammonoids generally have a flat spiral. By the way, true ammonites in the strict sense didn't appear in the geological record until the late Triassic. Carboniferous ammonoids are mostly goniatites.

Thank you so much for the reply! I found it very informative.

 

I had discovered an "ammonite" in a pile of rocks we got to build a pond. It's most likely carboniferous, so it would be a goniaite then. Very interesting. I guess will knowledgeable people on this forum, you learn something new every day.

 

And yes, gastropod was my original guess for years, but I looked back on this specimen and just wanted to be sure.

Edited November 27, 2024 by Kohler Palaeontology