Echinocorys from Les Andelys, France

[Mart1980]

Today I receive some Echinocorys

(Leske, 1778) sea urchins. Some still in their flint matrix. I am in love with their color variety. They were found in the fields around Les Andelys along the River Seine. Parasitic worm tunnels are visible on some sea urchins. Also contain some mini calcite crystals, which are clearly visible in the sunlight.

 

For my sea urchin collection and welcome addition. I would like to identify them by species, who can help me with good online documentation about these sea urchins?

 

I will also post detailed pictures in the topic so I can get some help. This will follow when I have better light and time. I like to hear when people recognize species 

 

 

 

 

 

 

 

 

 

Edited October 25, 2022 by Mart1980

[Mart1980]

I see now that the topic is in the wrong category. Can the topic be moved to Fossil ID? Apologies!

[JohnJ]

Moved.  No problem.  

[JohnJ]

The Echinoid Directory is always helpful.  However, your specimens are molds of the inside of the echinoid, so species assignment will be speculative.

 

@caterpillar

[caterpillar]

Identifying an echinoid with only an internal mold is difficult because the characters of the species are found on the shell.

Generally, these Echinocorys are assigned to the species scutata

[Mart1980]

I know there is a conclusion (Hayward 1941) that only one (variable) species can be distinguished, namely Echinocorys scutata. Thereby they distinguish one into five 'formae', I hope to be able to bring mine to a 'formae' name. Yes they are molds, but still with a lot of details and some are clear enough in shape to perhaps assign to a 'formae'. The pointed ones in particular go well with 'perconica'.

 

As a species I therefore leave them on Echinocorys scutata. There will certainly be more information in the future, the science surrounding Echinocorys is far from being resolved.

[caterpillar]

The shape is not a determining criterion in sea urchins. Within the same species, we can find tall, round, flatter, more or less conical shapes. An internal mold does not allow to see the arrangement of the plates, the fascioles, the pores, so many characteristics useful for the determination. Yes, the scutata species is a catchall but with your specimens, we cannot go further

[Mart1980]

The opinion I now follow is that all these sea urchins are Echinocorys scutata. I only look at which forms exist within this species. Surely five forms would have been studied there.

 

I agree that the shape of a sea urchin 'alone' means nothing. But together with a sum of still visible characteristics one can come a long way with flint sea urchins. In addition, a lot of the characteristics are visible in many of these sea urchins. Although it is difficult to see in a photo, there are two examples.

 

 

 

But maybe my search will lead to nothing in the end. Then at least the color diversity brings life to my sea urchin display, with mostly white marl sea urchins.

Edited October 27, 2022 by Mart1980