Hollow Hollardops: Extreme Trilobite Prep

[Biotalker]

I came across a couple of trilobites that have been prepped to the extreme. Except for a ventral "support bar", the matrix has been completely removed. Perhaps Hollardops and Reedops have some unusual characteristic to their skins to withstand the double-sided treatment. Light on the other side of the carapace will shine through at the thinnest sections. Makes for a cool display! Here are the Hollardops pics. 

[Biotalker]

and the Reedops prep.

[Sjfriend]

Wow. I can't imagine the prep time involved!

[Kane]

3 hours ago, Biotalker said:

Perhaps Hollardops and Reedops have some unusual characteristic to their skins to withstand the double-sided treatment.

Nothing unusual per se, although some trilobites do have a thicker shell to withstand this form of preparation process. What is generally used in these scenarios is applying something to strengthen the dorsal shell, such as Locktite or similar product. These "flying trilobites" have become more common among Moroccan offerings in the last few years. 

[Tidgy's Dad]

2 hours ago, Kane said:

Nothing unusual per se, although some trilobites do have a thicker shell to withstand this form of preparation process. What is generally used in these scenarios is applying something to strengthen the dorsal shell, such as Locktite or similar product. These "flying trilobites" have become more common among Moroccan offerings in the last few years. 

Yes, the fossil warehouses in Erfoud have shelves full of them.

[FranzBernhard]

32 minutes ago, Tidgy's Dad said:

Yes, the fossil warehouses in Erfoud have shelves full of them.

What do you think, are all of these genuine?
Franz Bernhard

[Tidgy's Dad]

1 hour ago, FranzBernhard said:

What do you think, are all of these genuine?
Franz Bernhard

Well, I don't know about all, but I think most of them are real :

 

[Biotalker]

3 hours ago, Kane said:

What is generally used in these scenarios is applying something to strengthen the dorsal shell, such as Locktite or similar product.

 

Clever! 

[Biotalker]

I wonder if the matrix behind the eyes could be removed and then light might (once again!) shine through those lenses. That ought to raise its visual appeal and potential trilobite vision/brain experiments.  

[Kane]

Yes, this has been done. In fact, any preparation of a ventrally oriented trilobite will see the removal of all matrix on the ventral side, including any covering the inside of the eyes. As for experimentation, there is abundant literature on trilobite eyes, and the customary method has been in performing thin slicing or using advanced imaging technologies. 

[fossilhunter21]

Wow! Whoever prepped these must have been very skilled! Those are some awesome displays peices.

 

-Micah

 

 

 

[mr.cheese]

I love those! @Tidgy's Dadwould you happen to have a name or two of people who may be able to supply this type of prepped trilobite? I deal with a man who buys from Morocco so he might well know them as I think they would look amazing in my shop as I am always trying to find something a little different.

[Kane]

Just to add if it was not clear: any seller recommendations should be done over PM.

[Biotalker]

Just for fun, here is a section through half of an adult fruitfly's brain, with the neuron nuclei stained dark. Imagine a trilobite having something like this behind its eye, except physically larger but perhaps simpler in organization (swimmers not fliers). The R7, R8 region = photoreceptors, L = lamina, M = medulla, LC = optic lobula complex, all devoted to receiving and processing visual information, BR = brain. Roughly, raw visual information from the photoreceptors gets transmitted to hierarchical levels of processing.

[Tidgy's Dad]

16 hours ago, Biotalker said:

Just for fun, here is a section through half of an adult fruitfly's brain, with the neuron nuclei stained dark. Imagine a trilobite having something like this behind its eye, except physically larger but perhaps simpler in organization (swimmers not fliers). The R7, R8 region = photoreceptors, L = lamina, M = medulla, LC = optic lobula complex, all devoted to receiving and processing visual information, BR = brain. Roughly, raw visual information from the photoreceptors gets transmitted to hierarchical levels of processing.

 

I seem to recall reading somewhere that trilobites heads were filled mostly with their stomach and feeding apparatus and there wasn't much room left for much more than a ganglion. The rest of the brain was distributed in bits down the pleurae. @piranha, I'm probably talking nonsense. 

[Kane]

Just for orientation purposes, these diagrams are from the revised Treatise O: Arthropoda (Moore, 1997). There is also a fairly comprehensive discussion on eyes in this essential text. 

 

 

 

 

[Biotalker]

See: https://www.nature.com/articles/s41598-021-98740-z

A 390 million-year-old hyper-compound eye in Devonian phacopid trilobites

B. Schoenemann, E. N. K. Clarkson, C. Bartels, W. Südkamp, G. E. Rössner & U. Ryck (2021)

 

Using X-ray analysis, striations extending from the eyes in certain very rare trilobites are visualized and are directed toward the mid cephalon. Termed “fibers”, they are thought to be neural and not gills (as had been previously proposed). The data pic shows such fibers from one particular German phacopid trilobite. The model pic shows the authors’ idea to explain the structures visualized. Although the data doesn’t penetrate into the glabella and therefore can’t say too much about a trilobite brain, clearly such a remarkable visual system would require a fair amount of processing circuitry for the organism to interpret and respond to its visual input. Trilobites don’t fly and so may not need such a degree of processing as seen in the fruit fly brain comparison above. Who knows, maybe you will find the first pyritized trilobite brain!

[Biotalker]

Sorry, "d" above is the trilobite model, the "e" represents known basic ommatidium structure.