IsaacTheFossilMan Posted November 1, 2021 Share Posted November 1, 2021 Hey! I'd like some help with some recurring Cotswold brachiopods. Great Oolite group; Middle Jurassic (Bajocian - Callovian). I've grouped them into 4 or 5 species / clades, based on their morphology. Species A - strongly ribbed, crystalline calcite. The specimen in my profile picture! (obviously not a good picture, included to show the great size range) A huge one! Predated upon: Species B: calcite, very spherical, non-ribbed but prominent growth lines Species C: almost completely spherical, unknown mineral, no ribs Species D: small, typically crushed, very flat, no ribs Species E: only a single valve found, very prominent growth lines. is either a bivalve, but it could be part of species B (more prep needed); the shape holds the exact same shape as the upper valve of the other species B items. That's all! @Tidgy's Dad, wanna have a crack? I know you've hunted here before! 1 ~ Isaac; www.isaactfm.com "Don't move! He can't see us if we don't move!" - Alan Grant Come to the spring that is The Fossil Forum, where the stream of warmth and knowledge never runs dry. Link to comment Share on other sites More sharing options...
Misha Posted November 2, 2021 Share Posted November 2, 2021 Can't help with the IDs but nice finds! Those are some cool looking Rhynchonellids and Terebratulids Link to comment Share on other sites More sharing options...
IsaacTheFossilMan Posted November 2, 2021 Author Share Posted November 2, 2021 11 hours ago, Misha said: Can't help with the IDs but nice finds! Those are some cool looking Rhynchonellids and Terebratulids Thanks! I have absolutely hundreds, the Cotswolds really are a gorgeous place to hunt! Yeap, I got them down to Rhynchonellida and Terebratulida ~ Isaac; www.isaactfm.com "Don't move! He can't see us if we don't move!" - Alan Grant Come to the spring that is The Fossil Forum, where the stream of warmth and knowledge never runs dry. Link to comment Share on other sites More sharing options...
IsaacTheFossilMan Posted November 5, 2021 Author Share Posted November 5, 2021 Hate to re-ping, but do you have anything to say @Tidgy's Dad? Some of the fossils I'm sending for secret santa contain are similar, and an ID would be nice to send off... If you don't have anything, that is okay! Cheers ~ Isaac; www.isaactfm.com "Don't move! He can't see us if we don't move!" - Alan Grant Come to the spring that is The Fossil Forum, where the stream of warmth and knowledge never runs dry. Link to comment Share on other sites More sharing options...
Tidgy's Dad Posted November 5, 2021 Share Posted November 5, 2021 Sorry, I somehow missed your first alert. I've been a bit busy. Can you give me a more precise location, please? By PM if you don't want to reveal it on the open forum. 1 Life's Good! Tortoise Friend. Link to comment Share on other sites More sharing options...
IsaacTheFossilMan Posted November 5, 2021 Author Share Posted November 5, 2021 (edited) 1 hour ago, Tidgy's Dad said: Sorry, I somehow missed your first alert. I've been a bit busy. Can you give me a more precise location, please? By PM if you don't want to reveal it on the open forum. Of course, no worries. These are the Inferior Oolite group, Burton-Limestone. Bajocian. Edited November 5, 2021 by IsaacTheFossilMan ~ Isaac; www.isaactfm.com "Don't move! He can't see us if we don't move!" - Alan Grant Come to the spring that is The Fossil Forum, where the stream of warmth and knowledge never runs dry. Link to comment Share on other sites More sharing options...
Tidgy's Dad Posted November 5, 2021 Share Posted November 5, 2021 1 hour ago, IsaacTheFossilMan said: Of course, no worries. These are the Great Oolite group! Oh, for goodness sake! I can read you know. But the Great Oolite Group outcrops in places over half of southern England and contains about fifteen Formations. So I asked you for a location - where they were actually found- to help narrow it down a bit. Where in the Cotswolds? Life's Good! Tortoise Friend. Link to comment Share on other sites More sharing options...
IsaacTheFossilMan Posted November 5, 2021 Author Share Posted November 5, 2021 5 minutes ago, Tidgy's Dad said: Oh, for goodness sake! I can read you know. But the Great Oolite Group outcrops in places over half of southern England and contains about fifteen Formations. So I asked you for a location - where they were actually found- to help narrow it down a bit. Where in the Cotswolds? Ah, my bad, sorry! Ummm, I'm not quite sure, they were quarried quite a while ago, so it could really be... anywhere. I'm sorry for the misunderstanding Adam! 1 ~ Isaac; www.isaactfm.com "Don't move! He can't see us if we don't move!" - Alan Grant Come to the spring that is The Fossil Forum, where the stream of warmth and knowledge never runs dry. Link to comment Share on other sites More sharing options...
IsaacTheFossilMan Posted November 5, 2021 Author Share Posted November 5, 2021 Got one!!! Species C is Sphaeroidothyris sphaeroidalis, based on other finds from the area. ~ Isaac; www.isaactfm.com "Don't move! He can't see us if we don't move!" - Alan Grant Come to the spring that is The Fossil Forum, where the stream of warmth and knowledge never runs dry. Link to comment Share on other sites More sharing options...
Tidgy's Dad Posted November 5, 2021 Share Posted November 5, 2021 1 hour ago, IsaacTheFossilMan said: Got one!!! Species C is Sphaeroidothyris sphaeroidalis, based on other finds from the area. No you haven't, I'm afraid. The accepted name is now Sphaeroidothyris arabica Cooper 1989. It could be this, but how do you know it's Great Oolite and not Inferior Oolite? And even it is Great Oolite, terebratulids and rhynchonellids were still very diverse at this time, it was only after this that the diversity declined. And there is a lot of variation within a species. I'm afraid that with no more precise locality information or known formation it's just guesswork. Sorry. 1 Life's Good! Tortoise Friend. Link to comment Share on other sites More sharing options...
IsaacTheFossilMan Posted November 5, 2021 Author Share Posted November 5, 2021 17 minutes ago, Tidgy's Dad said: No you haven't, I'm afraid. The accepted name is now Sphaeroidothyris arabica Cooper 1989. It could be this, but how do you know it's Great Oolite and not Inferior Oolite? And even it is Great Oolite, terebratulids and rhynchonellids were still very diverse at this time, it was only after this that the diversity declined. And there is a lot of variation within a species. I'm afraid that with no more precise locality information or known formation it's just guesswork. Sorry. Hey, I edited the previous message a while back, it is indeed Inferior With a more precise locality, too. ~ Isaac; www.isaactfm.com "Don't move! He can't see us if we don't move!" - Alan Grant Come to the spring that is The Fossil Forum, where the stream of warmth and knowledge never runs dry. Link to comment Share on other sites More sharing options...
Tidgy's Dad Posted November 5, 2021 Share Posted November 5, 2021 1 hour ago, IsaacTheFossilMan said: Hey, I edited the previous message a while back, it is indeed Inferior With a more precise locality, too. So, you edited a message after I'd replied to it and now need me to find which one you've edited so I can find the locality? And you seem averse to saying, "Thank you". How did you suddenly get this information, please? Anyway, if the locality, which I still can't find mentioned, is Burton Bradstock, or the area somewhere around where the Burton Limestone outcrops, then your rhynchonellids are Goniorhynchia boueti. The more triangular terebratulids will be Avonothyris langtonensis, and the rounder ones Sphaeroidothyris arabica. The last ones could be young or just small Digonella sp. 1 Life's Good! Tortoise Friend. Link to comment Share on other sites More sharing options...
IsaacTheFossilMan Posted November 6, 2021 Author Share Posted November 6, 2021 13 hours ago, Tidgy's Dad said: So, you edited a message after I'd replied to it and now need me to find which one you've edited so I can find the locality? And you seem averse to saying, "Thank you". How did you suddenly get this information, please? Anyway, if the locality, which I still can't find mentioned, is Burton Bradstock, or the area somewhere around where the Burton Limestone outcrops, then your rhynchonellids are Goniorhynchia boueti. The more triangular terebratulids will be Avonothyris langtonensis, and the rounder ones Sphaeroidothyris arabica. The last ones could be young or just small Digonella sp. Hey. On my end, I edited the message before yours came through, so, apologies for that! Thank you for the information. I did consider G. boueti and A. langtonensis, however the beak of my specimen are straight, unlike the images I've found of these species. Sorry for everything, again, I must've been silly tired yesterday. Thank you for putting up with this. ~ Isaac; www.isaactfm.com "Don't move! He can't see us if we don't move!" - Alan Grant Come to the spring that is The Fossil Forum, where the stream of warmth and knowledge never runs dry. Link to comment Share on other sites More sharing options...
IsaacTheFossilMan Posted November 15, 2021 Author Share Posted November 15, 2021 (edited) On 11/5/2021 at 10:35 PM, Tidgy's Dad said: Goniorhynchia boueti Bumping this post to say that I've just found out this is an old homotypic synonym, as shown here https://www.gbif.org/species/8611756 The new name is Rhynchonella boueti. Avonothyris langtonensis (https://www.gbif.org/species/8707145) is now Terebratula langtonensis. However, labelling a specimen with the old name as well could be beneficial. I might just say "Terebratula (erat Avonothyris) langtonensis". See these charts: Edited November 15, 2021 by IsaacTheFossilMan ~ Isaac; www.isaactfm.com "Don't move! He can't see us if we don't move!" - Alan Grant Come to the spring that is The Fossil Forum, where the stream of warmth and knowledge never runs dry. Link to comment Share on other sites More sharing options...
Tidgy's Dad Posted November 15, 2021 Share Posted November 15, 2021 This is the same as a subjective synonym. It just means that they are acknowledged to be the same species but it depends if you're a lumper or a splitter and whether you believe Rhynchonella and Terebratula are still valid for the numerous genera they have now been separated into. I am of the opinion that both were used as bucket taxa back in the day, everything that was a classic look rhynchonellid was Rhynchonella and everything the 'lamp shell' terebratulid was Terebratula, and never mind internal details. In these instances, I stick with Avonothyris and Goniorhynchia, as do most modern researchers. Life's Good! Tortoise Friend. Link to comment Share on other sites More sharing options...
IsaacTheFossilMan Posted November 16, 2021 Author Share Posted November 16, 2021 21 hours ago, Tidgy's Dad said: This is the same as a subjective synonym. It just means that they are acknowledged to be the same species but it depends if you're a lumper or a splitter and whether you believe Rhynchonella and Terebratula are still valid for the numerous genera they have now been separated into. I am of the opinion that both were used as bucket taxa back in the day, everything that was a classic look rhynchonellid was Rhynchonella and everything the 'lamp shell' terebratulid was Terebratula, and never mind internal details. In these instances, I stick with Avonothyris and Goniorhynchia, as do most modern researchers. That makes a lot more sense. I suspected they were bucket-taxa, thank you very much for the input. Time to undo the ERAT hah! ~ Isaac; www.isaactfm.com "Don't move! He can't see us if we don't move!" - Alan Grant Come to the spring that is The Fossil Forum, where the stream of warmth and knowledge never runs dry. Link to comment Share on other sites More sharing options...
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