sander Posted March 22, 2015 Share Posted March 22, 2015 Hi all, I recently acquired more Epidavros Triassic Ammonites, but unfortunately the seller didn't know their names. Can someone give them an ID? photo 3 is the edge of the leftmost ammonite on the upper row, photo 4 is a close up of the leftmost ammonite on the lower row. Thank you, Sander Link to comment Share on other sites More sharing options...
andreas Posted March 22, 2015 Share Posted March 22, 2015 Hello, From left, upper row: Sturia sp. 2x(probably Sturia sansovinii), Gymnites(Epigymnites cf.ecki) second row: 1x?, Arcestes sp., Monophyllites sp.(M. sphaerophyllum or M. wengensis),?Atractites, Aulacoceras or Michelinoceras, The exact species to tell is difficult because you have to know the exact horizon where the ammonoids come from. There are several layers with ammonoids in Epidauros. This link will help you a little. Unfortunly it is not in english language but pics and species names are given. Kind regards Andreas 1 Link to comment Share on other sites More sharing options...
sander Posted March 22, 2015 Author Share Posted March 22, 2015 Hi Andreas, The two Sturia's are different, one has ribs like cladiscites (Like a Vinyl record) and the other one has wavy ribs like in Cleoniceras, only on the ventral side and near the middle of the ammonite it has vinyl record like ribs, and it has a 'hilly' surface, whiel the other vinyl record like ammonite has a flat surface. So I don't think that they belong to the same species. the leftern ammonite on the lower row has vague ribs and flattened tubercles near the middle of the amonite, maybe this will give you an idea on what they are? Gr, sander Link to comment Share on other sites More sharing options...
sander Posted March 22, 2015 Author Share Posted March 22, 2015 (edited) I've had a look at the paper you send (thanks for that) and I come to this conclusion: from upper left to lower right: Sturia semiarata Sturia semiarata Epigymnites ecki ?Ptychites? Proarcestes esinensis and the last one is not Alaucoceras (that one has ribs, this one is smooth) what are the diferences between Michelinoceras and Atractites? Somewhere I read that Michelinoceras is a orthoceras kind of animal and that they have their siphon in the middle of the cone. and that in Alaucoceras and Atractites this is more near the edge. In my specimen there is a small dimple which is more to the edge then perfectly in the middle, so if this is true it is Atractites? And which species should it be then? I will go try to see which Ptychites this might be. Is there a list of all these ammonites species where in it is stated from which stage they should be? (Ladinian, Carnian, Norian) Gr, Sander Edited March 22, 2015 by sander Link to comment Share on other sites More sharing options...
sander Posted March 22, 2015 Author Share Posted March 22, 2015 Hi Andreas, I've looked at the other ammonites from this location that I already have and I think they should be this: 1:Ptychites oppeli or opulentus 2:Proarcestes cf. subtridentinus 3:Megaphyllites procerus 4:Proarcestes esinensis 5:Proarcestes esinensis Do you agree? Gr, Sander Link to comment Share on other sites More sharing options...
andreas Posted March 22, 2015 Share Posted March 22, 2015 Hi Sander, for Sturia you can read the original description in Mojsisovics "Die Cephalopoden der Mediterranen Triasprovinz". But Sturia has a very long stratigraphic range from Anisian to Ladinian. According to Mojs. Sturia semiarata(Ladinian) show in juvenile stage wavy ribs like the first ammonoid. Lines/Striae are only visible on the Venter and around the umbilicus. S. semiarata is older(Anisian) and show Lines all about the chamber. I personally found morphs of Sturia in a clear Ladinian Location which do show both species characteristics indipendent from their size. So I personally tend to name after the stratigraphic layer. Anisian is S. sansovinii, Ladinian ones are S. semiarata. I am not very firm with orthocone Nautiloidea like Aulacoceras and Atractites. Both genera do have the Sipho near the side. Orthoceras do have a middle sipho. Newer literature exist from N. Mariotti and S. Pignatti. Maybe you can find some papers in the net. If not pm me. The unknown ammonoid could maybe be a Ptychites sp. but this is very unsure. You do not know for sure that all species came from the same layer. So I would give them all a cf. before the species name. The genus names on your last pics seem correct, but I cannot define the exact species name without layer and the other faunalspectrum. So please add sp. after the genus names. Kind regards Andreas Link to comment Share on other sites More sharing options...
sander Posted March 22, 2015 Author Share Posted March 22, 2015 I tried to translate a bit of the articles about the ammonites, and I found out that Avíolo (can't spell in greek here) means Anisio = Anisian and ^adívIo means Ladinio = Ladinian. searching every text about the ammonite genus and species named above I came out at this list: Sturia semiarata = Ladinian Epigymnites ecki = Anisian Ptychites oppeli or opulentus = Anisian Proarcestes esinensis = Anisian-Ladinian (couldn't really translate that text piece about it's age) Megaphylites procerus = Anisian I always thought that the Epidavros locality yielded ammonites from Ladinian and Carnian age, but they are almost all Anisian in age. is this correct? Gr, Sander Link to comment Share on other sites More sharing options...
andreas Posted March 22, 2015 Share Posted March 22, 2015 In this work the focus was given to the lower part of Hallstatt limestone there. So it seems there is a preponderance of Anisian genera. At the end of the work, right before the tables, a short abstract in english and in german language is given. Link to comment Share on other sites More sharing options...
sander Posted March 23, 2015 Author Share Posted March 23, 2015 I've made a few more photo's of the Michelinoceras/Atractites, Maybe it is clear now? on photo 2 you can see the siphon running down on the places where the black layer is missing. Link to comment Share on other sites More sharing options...
sander Posted March 23, 2015 Author Share Posted March 23, 2015 And some more photo's of the ?Ptychites? Gr, Sander Link to comment Share on other sites More sharing options...
andreas Posted March 23, 2015 Share Posted March 23, 2015 (edited) I would say Atractites. Link leads to a newer work about Atractites. The summary of the previous works is interesting. The ?Ptychites is not to id. Do prep the umbilicus out and grind the backside to see the lobes. Then it should be possible to id the specimen. kind regards Andreas Edited March 23, 2015 by andreas Link to comment Share on other sites More sharing options...
sander Posted March 23, 2015 Author Share Posted March 23, 2015 Hi Andreas, Thanks for the ID. I have only got a dremel with a carbon disc and some used dental tooth scrapers/picks, so I think that I will postpone the preping of this ammonite until I have better equipment. about the Atractites, I found this old article about triassic Epidaurus: https://archive.org/stream/palaeontographic58cass#page/n0/mode/2up for the Trinodosus-schichten (Anisian?) it mentions Atractites obeliscus, From the Wengener-schichten (Ladinian?) it is Atractites boeckhi, and from the lower Carnian he mentions Atractites ausseeanus and Atractites argivus. When looking at the other fossil from this batch (those from post 1) I see that most do not appear in the Carnian, and also some are missing in the Anisian layers. Might this whole batch come from the Wengener Schichten (and thus is Ladinian and that means that this is Atractites boeckhi)? or is this old publication outdated and too simple? Gr, Sander Link to comment Share on other sites More sharing options...
sander Posted March 29, 2016 Author Share Posted March 29, 2016 (edited) Dear Forum members, It is a year later and I have managed to get all the other triassic ammonites in the collection which i could only partly buy last year. There are three new ammonites, and I think that , when looking at the age, that the whole collection could come from the very fossil rich Nevadites zone of Anisian Epidavros. The first new fossil is probably a very flat (Epi)gymnites? with on the ventral lateral shoulder a slightly ribbed appearance. On the rear of this block is a partially complete ammonite, still encased in the matrix, of which I think it is a Nevadites. the second new ammonite is probably a ptychitoid, it has very fine striations, finer than on Monophyllites. the third new one is a bit globular, and bigger than Arcestes like ammonites, I think it might be a Joannites. but the Nevadites along with the Sturia semiarata and forojulensis and Epigymnites ecki point to a probable age of the Nevadites zone, with all other ammonites in the collection of 10 (see photo 1) also possibly from this same zone. Do you guys agree? more photo's with ventral views are coming up as well. Thanks in advance, Sander Edited March 29, 2016 by sander Link to comment Share on other sites More sharing options...
sander Posted March 29, 2016 Author Share Posted March 29, 2016 the probable Nevadites Link to comment Share on other sites More sharing options...
sander Posted March 29, 2016 Author Share Posted March 29, 2016 photo 1-3: the second new ammonite, Ptychoid ammonite? Photo 4-5: the third new ammonite, a Joannites? Link to comment Share on other sites More sharing options...
sander Posted March 29, 2016 Author Share Posted March 29, 2016 photo 1: ventral view of the third new ammonite, Joannites? photo 2: ventral view of the Epigymnites ecki photo 3: Sturia semiarata photo 4: Sturia semiarata ventral view photo 5: Sturia forojulensis photo 6: Sturia forojulensis ventral view Link to comment Share on other sites More sharing options...
sander Posted March 29, 2016 Author Share Posted March 29, 2016 photo 1-2: Proarcestes sp? photo 3: Monophyllites sp. ventral view photo 4-5: possible Ptychoid ammonite. That's it, I hope this is enough to identify whether this whole batch might be from the same zone, or to see some ammonites that are much younger than this layer to prove me wrong. With the literature available to me I this is what I think, but I look forward to what you guys think of it. Thanks in advance, Sander Link to comment Share on other sites More sharing options...
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