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Showing results for tags 'micraster'.
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I have just bought these from a collector and the labels are a little jumbled. I have left them in the section they were in if there is a double set in one and no label in another! I have enough labels to go round a little help with where is needed! I can obviously take more photos if required. There is some beautiful ones in here, I am really pleased with them.
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From the album: Echinodermata
5x5cm. cortestudinarium zone Upper Chalk Formation Coniacian Late Cretaceous From Cuckmere, Sussex, England -
From the album: Echinodermata
4x4.5x2.5cm. Turonian Late Cretaceous Paris Basin-
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- paris basin
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I found this Phlycticrioceras trinodosum heteromorph specimen in June of 2018 whilst hunting the middle/upper Coniacian Atco formation. It is the largest fragment of this species that I am aware of, having a whorl height of 51 mm as opposed to 47 mm of the largest fragment I've seen published. This genus is a bigger, rarer, and (mostly) younger cousin of Allocrioceras. I sent pictures of it to Keith Minor and he pointed out that there was also an echinoid sticking out of the specimen, something which I had totally missed! With much of the echinoid still stuck in the living chamber it is hard to get a definitive ID. But because it has such a shallow anterior ambulacra, which gives the anterior end a more smooth rather than definitive heart shape, he ruled out both Mecaster texanus and batensis. He suggested Micraster since the site has a strong European component in both the bivalve and ammonite faunas, and because the periproct side has the right shape. From finding other, although not as well preserved specimens that show similar morphology he appears to be right. I have yet to confirm this ID with Andrew Smith, but either way I think the piece is worth showing. And reading this thread got me thinking about how this could have happened and what effect it could have had on the echinoid's preservation. My thought is that because irregular echinoids lived and today still live most of their lives burrowing in the sediment it is unlikely that it would have crawled into the living chamber, but instead that it was blown into it post-mortem via currents that had dredged it out of the sediment. I already know that this site was a high energy environment from my other finds here so this seems the most likely possibility to me. But because of the fact there is still at least one spine still attached to the specimen it could not have been swept up from the sediment too long after death or all of its hairlike spines would have blown away. I do, however, find it interesting that it is positioned anterior first with its posterior towards the aperture, the position I would expect to see it in if it had indeed crawled into the shell. The specimen is also the best preserved echinoid from this site so far. Despite the ammonites being generally well preserved and not too crushed, most of the echinoids that I have from the site are terribly crushed, flakey, and often infested with rotting pyrite. I think being encapsulated in the chamber very much reduced those effects. Even though the ammonite and the echinoid are a bit crushed, the echinoid would have probably been worse off otherwise. The heteromorph fragment length is 70 mm and the whorl breadth, being a bit crushed, is 13 mm. I would think that this specimen, with its open planispiral coiling, would would have been at least over a foot in diameter when complete. It is the robust (female) morph of the species with a rib index of 5½. For comparison in Fig. 1 I pictured it with my most complete P. trinodosum specimen. From the part of the echinoid that is exposed I can measure 25 mm in length, 25 in width, and a thickness of 8 mm. I have also found abundant yet scattered fish remains at the site, so perhaps one day an ammonite-fish will come my way. But until then, anyone else got ammonite-echinoids to show? Fig. 1. Fig. 2.
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- and drink em bot up
- atco formation
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I hadn't seen an echinoid with beekite before so I had to buy it. Micraster glyphus?, Campanian, Höver, Germany.
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From the album: Haute normandie - April 2018
Last hunt from Normandy cretaceous : best of echinoids -
Christmas holyday trip to the northern coast of France
Manticocerasman posted a topic in Fossil Hunting Trips
At the start of the Christmas holiday I went with my girlfriend on a fossil hunting weekend to the French coast. first stop was the “pointe au oies” with jurassic deposits. apart from a small echinoid we didn't find a lot of decent fossils. after lunch we went 80km more to the south to a little hotel above the cretaceous cliffs near Ault. Since it was still light when we got there we made a 1st prospection on the beach and quickly found a few nice echinoids ( Micraster sp. ) the next day further inspection of the boulders on the beach delivered even more beautiful echinoid specimens. most of them very well preserved. This was a successful trip, I’ll certainly go back there next year.- 18 replies
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- cretaceous
- france
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From the album: Senneville-sur-Fécamp
double micraster decipiens 2 view 3 - august 2015 :heart urchin from the turonian chalk of normandy - Senneville sur Fécamp -Turonian - Cretaceous- 1 comment
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From the album: Senneville-sur-Fécamp
double micraster decipiens 1 view 2 - august 2015 :heart urchin from the turonian chalk of normandy - Senneville sur Fécamp -Turonian - Cretaceous-
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- Cretaceous
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From the album: Senneville-sur-Fécamp
double micraster decipiens 1 view 1 - august 2015 :heart urchin from the turonian chalk of normandy - Senneville sur Fécamp -Turonian - Cretaceous-
- chalk
- Cretaceous
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From the album: Senneville-sur-Fécamp
Micraster decipiens 2 - august 2015 :heart urchin from the turonian chalk of normandy - Senneville sur Fécamp -Turonian - Cretaceous-
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From the album: Senneville-sur-Fécamp
Micraster decipiens 1 - august 2015 :heart urchin from the turonian chalk of normandy - Senneville sur Fécamp -Turonian - Cretaceous-
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- Cretaceous
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From the album: Senneville-sur-Fécamp
Highlights of august 2015 hunt-
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- Cretaceous
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From the album: Senneville-sur-Fécamp
double micraster decipiens 2 view 2 - august 2015 :heart urchin from the turonian chalk of normandy - Senneville sur Fécamp -Turonian - Cretaceous-
- chalk
- Cretaceous
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(and 7 more)
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From the album: Senneville-sur-Fécamp
double micraster decipiens 2 view 1 - august 2015 :heart urchin from the turonian chalk of normandy - Senneville sur Fécamp -Turonian - Cretaceous-
- chalk
- Cretaceous
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From the album: Senneville-sur-Fécamp
Double micraster decipiens : heart urchin from the turonian chalk of normandy - Senneville sur Fécamp -Turonian - Cretaceous- 1 comment
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- chalk
- cretaceous
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From the album: Senneville-sur-Fécamp
Best of my september hunt from the turonian chalk of normandy - Senneville sur Fécamp -Turonian - Cretaceous-
- chalk
- cretaceous
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From the album: Senneville-sur-Fécamp
Micraster sp (leskei?) : heart urchin from the turonian chalk of normandy - Senneville sur Fécamp -Turonian - Cretaceous-
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- cretaceous
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From the album: Senneville-sur-Fécamp
Double micraster decipiens : heart urchin from the turonian chalk of normandy - Senneville sur Fécamp -Turonian - Cretaceous-
- chalk
- cretaceous
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(and 8 more)
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From the album: Senneville-sur-Fécamp
Double micraster decipiens : heart urchin from the turonian chalk of normandy - Senneville sur Fécamp -Turonian - Cretaceous-
- chalk
- cretaceous
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(and 8 more)
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From the album: Senneville-sur-Fécamp
Micraster decipiens : heart urchin from the turonian chalk of normandy - Senneville sur Fécamp -Turonian - Cretaceous-
- chalk
- cretaceous
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(and 8 more)
Tagged with:
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From the album: Senneville-sur-Fécamp
Micraster decipiens : heart urchin from the turonian chalk of normandy - Senneville sur Fécamp -Turonian - Cretaceous-
- chalk
- cretaceous
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(and 8 more)
Tagged with:
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From the album: Senneville-sur-Fécamp
Micraster decipiens : heart urchin from the turonian chalk of normandy - Senneville sur Fécamp -Turonian - Cretaceous-
- chalk
- cretaceous
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(and 8 more)
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From the album: Senneville-sur-Fécamp
Micraster decipiens and 1 echinocorys gravesi (center) from the turonian chalk of normandy - Senneville sur Fécamp -Turonian - Cretaceous- 1 comment
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- chalk
- cretaceous
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From the album: Senneville-sur-Fécamp
Micraster decipiens : heart urchin from the turonian chalk of normandy - Senneville sur Fécamp -Turonian - Cretaceous-
- chalk
- cretaceous
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(and 8 more)
Tagged with: