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Fred
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Registration Date: 24.10.2008
Posts: 238

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Don't you just hate it when some part of the trilobite is not there (or not where you think it should be).
I just had these 3 in a row. The pygidium is finished. Why not? Even partials can be of value.

I'll see whether I can find the rest of these bugs...

Fred has attached these images (downsized versions):
bum 1.jpg bum 2.jpg bum 3.jpg

28.02.2012 21:56 Fred is offline Send an Email to Fred Homepage of Fred Search for Posts by Fred Add Fred to your Buddy List
Jens Jens is a male
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Registration Date: 18.03.2007
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Hi Fred,

interesting trilobite, pitty that he is not complete, but its a rare one and give us some informations. For me the pygidium looks more phacopid than proetid.

Anyway, for the moment I have no guess, what a proetid-genus this bug could be.

regards,
Jens
28.02.2012 22:35 Jens is offline Send an Email to Jens Homepage of Jens Search for Posts by Jens Add Jens to your Buddy List
Fred
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Registration Date: 24.10.2008
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Thread Starter Thread Started by Fred
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For the record: the 3 pics are 3 different bugs, 2 Gerastos and one Reedops.
28.02.2012 22:49 Fred is offline Send an Email to Fred Homepage of Fred Search for Posts by Fred Add Fred to your Buddy List
Jens Jens is a male
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Hi Fred,

may be the position you used to show us the first bug was misleading, but it looks not after a typical Gerastos. The preglabella-field is extremly short and the glabella not strong inflated. In the Pragian are many different genera of Proetids known. May be you find something special. I'm not sure if Alberti found a Pragian Gerastos.

Please confirm that these bugs are from the Pragian;-)

regards,
Jens
29.02.2012 15:17 Jens is offline Send an Email to Jens Homepage of Jens Search for Posts by Jens Add Jens to your Buddy List
Fred
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Registration Date: 24.10.2008
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Thread Starter Thread Started by Fred
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I refuse to confirm all these bugs are from the pragian. Glücklich5

Seriously, sorry for the confusion. The first two are Gerastos from the lower eifelian, the last one is a small Reedops I found at Atchana.

What unites all three of them, is that they appeared to be very promising specimens that turned out to be not-so-good after all. When presenting Moroccan material at our dutch forum, I was asked repeatedly whether all trilobites in these layers are complete.

The answer is 'no' of course.

The purpose of presenting this side of the prepping story is to inform, but also to share ideas about them.
What would you do? Invest precious time in prepping some incomplete specimen or not?

Personally, I decided to make them low-priority, but prep one of them from time to time, as they might tell very interesting stories (e.g. about molting processes.

Attached a pic of the first specimen, from the side.

Fred has attached this image (reduced version):
ger.jpg

This post has been edited 1 time(s), it was last edited by Fred: 01.03.2012 13:56.

29.02.2012 20:23 Fred is offline Send an Email to Fred Homepage of Fred Search for Posts by Fred Add Fred to your Buddy List
Jens Jens is a male
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Hi Fred,

ah, okay, thanks for the confusion;-) Now I understand, what you had in mind by presenting us this material.

Its a good idea to speak about our material. I think we can say, that normally trilobite remains are not complete, but in several horizons the chance to find something complete is much higher than in other ones. We discussed that phenomena under taphonomical interpretations. In Morocco the trilobite hunters look especially in horizons with many complete trilobites, trilobite couches. Especially they search for rare, big and spiny bugs, but nowadays also the small ones become interesting. However.

I know some preparators who stop the preparation when problems with the articulation or a missing librigena becomes clear. Its reasonable because the lifetime of a human is limited, but there is a unlimited amount of complete trilobites out there.
I prepare sometimes also incomplete trilobites, but then they have to be somewhat special, e.g. rare species or I want to know what is behind a cross-section to get the info what trilobite it is.

But incomplete trilobites are not really good for motivation to finish a preparation, especially when you have dozens of other specimens in the pipe;-)

If preparators work on a commercial basis, than incomplete (common) trilobite are normally not worth to finish them, because the market is hard and incomplete trilobites are difficult to sell and bring not much money. Sometimes less than the prep-costs for the trilobite. So you can imagine what happens with such material -> Dummpost

regards,
Jens
01.03.2012 12:43 Jens is offline Send an Email to Jens Homepage of Jens Search for Posts by Jens Add Jens to your Buddy List
Fred
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Registration Date: 24.10.2008
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Thread Starter Thread Started by Fred
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I find slightly disarticulated specimens such as the middle one in my first post quite challenging to prep, and a useful learning experience for a beginner like me.
The challenge is to probe the remaining matrix for other parts as quick as possible, but without causing extensive damage when finding something. The experience gained from this exercise is the quick recognition of unexpected trilobite parts (e.g. like an unexpected second trilobite).

But I agree, too much of this kind of exercises can be just a waste of time.
01.03.2012 14:02 Fred is offline Send an Email to Fred Homepage of Fred Search for Posts by Fred Add Fred to your Buddy List
Jens Jens is a male
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Hi Fred,

you are definitely right, when you say that a disarticulated specimen is challenging. I agree, when you use such material for training purposes and may be, when finished such specimens give us valuable informations about molting or taphonomic processes. In this view also incomplete material can be very interesting.
I have also my scientific background and see some things in a different light. For instance Andrue hates pathological trilobites, especially rare species with such disharmonies hurt his eyes;-) May be he is joking, or not;-)
Anyway, its always necessary to train the prep-skill and I think You are not a beginner;-)

all the best and happy hunting,
Jens
01.03.2012 18:54 Jens is offline Send an Email to Jens Homepage of Jens Search for Posts by Jens Add Jens to your Buddy List
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