Allosaurus Posted February 17 Share Posted February 17 I picked up 3 ammonites last summer and was told they were from England, but with no additional information such as age or locality :(. I'm hoping someone out here might be able to help me ID them to genus or perhaps even have ideas as to where they originate. #1 Link to post Share on other sites
Ludwigia Posted February 17 Share Posted February 17 Hard to tell without the necessary information. #1 is indecipherable for me. #2 may be Garantiana or another Peresphinctid and #3 perhaps Dorsetensia. But those are both just wild guesses. 1 Link to post Share on other sites
caterpillar Posted February 17 Share Posted February 17 The 1 could be an Hildoceras. But as Roger said, difficult to tell without informations Link to post Share on other sites
Allosaurus Posted February 17 Author Share Posted February 17 Thanks everyone. Yeah, I figured it was a long shot, and I appreciate your input. I'll just notate them as unsure with question marks and the possible identifications. Link to post Share on other sites
dhiggi Posted February 17 Share Posted February 17 As mentioned above, number 1 has a few similarities to Hildoceras that we find along the Whitby coast. The matrix is totally different though Link to post Share on other sites
abyssunder Posted February 17 Share Posted February 17 Are you sure they can't be from Madadagascar? Link to post Share on other sites
Allosaurus Posted February 17 Author Share Posted February 17 1 hour ago, abyssunder said: Are you sure they can't be from Madadagascar? I won't say with certain as I didn't collect them, but I would be a little surprised if the locality was incorrect. I've never seen ammonites like these come from Madagascar. Have you see similar ones with a provenance out of Madagascar? Link to post Share on other sites
fifbrindacier Posted February 18 Share Posted February 18 All i can say is that you can write Jurassic for your identifications. And i agree the number two is a perisphinctid. Link to post Share on other sites
BentonlWalters Posted February 18 Share Posted February 18 Just a guess, but the colouring and preservation is very similar to Jurassic ammonites found in Somerset from the Beacon Limestone Formation at places like Kingstone (https://ukfossils.co.uk/2016/06/10/kingstone/) which is Pliensbachian to Toarcian in age. With this in mind the first appears to be Hildoceras sp. and the second probably Dactylioceras sp.. I'm less sure about the third one though. Hopefully this helps. Benton Link to post Share on other sites
Reconquistador Posted February 25 Share Posted February 25 Number 1: I would say, that it is Hildoceras. One can see lateral groove, which is not very common character. Some Hildoceras species are well known for it (other genera which posseses it, like Cleviceras, Parahildaites, Ochetoceras or other looks differently). Tricarinate-bisulcate venter is also well visible. By quadrate whorl section and only weak lateral groove, I would expect it to be Hildoceras lusitanicum. But I am not completelly sure about it. Number 2: This is much harder. It looks like Dactylioceras (Dactylioceras). And it not only looks like that, but as preservation is similar to the first one, they may come from the same locality and age and these genera occured together. I do not know how to identify species of this genus (with few exceptions), but this one is certainly not D. (D). praepositum, D. (D.) holandrei, or D. (D.) athleticum. It is quite similar to D. (D.) commune (which is quite common species as its name suggests) and many collectors would name it as such, but it could also be something different. Number 3: If it comes from the same locality and age, then it should be some Harpoceratinae indet. Link to post Share on other sites
IsaacTheFossilMan Posted February 25 Share Posted February 25 I can't help with ID, but, if they're from the UK, they'll be Jurassic. Link to post Share on other sites
will stevenson Posted February 25 Share Posted February 25 They look like they are from the beacon limestone fm. Of somerset, I can’t think of another formation With that preservation, if so the species would 1.hildoceras 2.dactylocerous 3. harpoceras Link to post Share on other sites
Reconquistador Posted February 26 Share Posted February 26 Harpoceras is highly probable. Sadly, ribs are poorly visible, but they seems to be falcate. If so, it is Harpoceras. If they are only falcoid, it can also be Cleviceras, but falcoid ribs are not excluding possibility of it being some species of Harpoceras. For Cleviceras, it also seems to be quite too evolute, but it might be still on the margin of possible variability of this genus. Comparison of falcoid and falcate ribs on Wikimedia Commons (my work) Link to post Share on other sites
Kosmoceras Posted February 26 Share Posted February 26 No doubt these are from Beacon Limestone Formation around Ilminster. 15 hours ago, IsaacTheFossilMan said: I can't help with ID, but, if they're from the UK, they'll be Jurassic. We do have Cretaceous ammonites in the UK too! Link to post Share on other sites
IsaacTheFossilMan Posted February 26 Share Posted February 26 2 minutes ago, Kosmoceras said: We do have Cretaceous ammonites in the UK too! Yes, but the preservation lends itself to Jurassic. Link to post Share on other sites
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now