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My trilobite of the week.


rew

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On 3/14/2020 at 8:43 PM, rew said:

Trilobite of the week #107 is the Silurian Encrinurus tuberculatus from the Much Wenlock Limestone Formation of Malvern, Worcestershire, England.

This is twice as long as my Encrinurus macrourus, and has a big axial spine.

 

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On 3/27/2020 at 5:48 PM, rew said:

Trilobite #112 is another Middle Devonian scutellid.  This is Scabriscutellum lahceni from the Timrhanrhart Formation at Foum Zguid, Morocco.  There are lenses visible in both eyes, with the left eye particularly well preserved.  The hypostome is visible and slightly detached.  There is an occipital spine, short stubby spines over the eyes, and prominent axial spines.

 

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On 3/27/2020 at 6:55 PM, rew said:

Here's a close up of the left eye.

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On 4/8/2020 at 6:14 PM, rew said:

Bonus mid-week trilobite #115 is another Chinese bug, Shergoldia laevigata, of Late Cambrian age and from the Sandu Formation at Jingxi, Guangxi, China.  It's not particularly pretty, but it's the only bug I have in the Tsinaniidae.

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Well, what a collection @rew !

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"On ne voit bien que par le coeur, l'essentiel est invisible pour les yeux." (Antoine de Saint-Exupéry)

"We only well see with the heart, the essential is invisible for the eyes."

 

In memory of Doren

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Trilobite of the week #116 is Crotalocephalus africanus, of Middle Devonian age from Jorf, Morocco.  This genus is distinguished from Crotalochephalina by having much larger pygidal spines, more splayed out pleural spines, and a broader but shallower head.

 

 

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Midweek bonus trilobite #117 is Bythicheilus typicum.  This is a small (9 mm) Middle Cambrian trilobite from the Spence Shale in Box Elder County, Utah.  If it weren't for the slightly separated free cheeks I'd rate this one as perfect.  As it is, it's pretty good.  It is in the Alokistocaridae, the same family that has Elrathia and Amecephalus.

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Trilobite of the week #118 is Lehua vinculum, a Late Ordovician cheirurid from the Ktaoua Formation near Zagor, Morocco.

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Trilobite of the week #119 is an undescribed Devonian Odontopleurid from Issoumour, Morocco that is labeled "aff. Laethoprusia sp." in my collection.  It is likely to wind up in that genus, but no guarantee.

 

 

 

 

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Trilobite of the week #120 is Cybele panderi, a Middle Ordovician member of the Encrinuridae from the Asery Level of the Lomaha quarry near St. Petersburg, Russia.  Like Asaphus kowalewskii this trilobite has long eye stalks.  They are unrelated species, this is a case of convergent evolution.

 

 

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I know many in your collection are spectacular, but for me, this one is especially wow!  The color, the contrast with the matrix, the awesome preservation, and especially those really cool eyes just make this one stand out for me. I don’t know how many more are yet to come, but this is my favorite so far. 

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On 5/7/2020 at 9:27 PM, ClearLake said:

I know many in your collection are spectacular, but for me, this one is especially wow!  The color, the contrast with the matrix, the awesome preservation, and especially those really cool eyes just make this one stand out for me. I don’t know how many more are yet to come, but this is my favorite so far. 

 

Thanks.  Russia has many awesome bugs, and Cybele panderi is on many trilobite collectors' want list (but due to its price, not necessarily on their "got" list).  The light caramel color of the Russian Ordovician bugs is an attractive feature, they always show up nicely against the matrix (the same is true of the Black Cat mountain Devonian trilobites from Oklahoma).  I have some fine Spence shale Cambrian bugs, but alas, at best they're dark gray on light gray.

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Trilobite of the week #121 is an early Ordovician Pliomerid from Nine Mile Shale in Eureka County, Nevada called Pseudocybele nasuta.  This bug has a small pointy rostrum and is longer and skinnier than the related Lemureops.

 

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This week is all about the Ordovician Fezouata Shale in Morocco.  Mid-week bonus trilobite #122 is the Early Ordovician Bathycheilus sp., from Ouled Slimane in the Zagora area.  As is often the case with this formation the shell preservation is rather crude, but sometimes the choice for a species is a crudely preserved trilobite or no trilobite.  This is a natural double.  Bathycheilus is the only genus I have in the family Bathycheilidae, which is in the order Phacopida.

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There's another bonus trilobite this week.  Trilobite #123 is Euloma sp., also of Early Ordovician age and from the Fezouata Shale of Ouled Slimane in the Zagora area of Morocco.  This trilobite is in the Eulomidae in the order Ptychopariida.  Again, the shell preservation is somewhat crude, typical of this site.

 

 

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Official trilobite of the week #124 is also Early Ordovician and is from the Fezouata Formation of Tinzouline in the Zagora Region of Morocco.  This is Parvilichas marochii, a cute little lichid.

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Trilobite of the week #125 is Calyptaulax callicephalus of Late Ordovician age from the Bobcaygeon Formation near Ottawa, Ontario.  This is a member of the Pterygometopidae so has shcizoid eyes.

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Trilobite of the week #126 is one of the greats -- the trilobites you show people to explain why you have this geeky hobby.  Of Middle Devonian age from the Tazoulait Formation at Taharajet, S-Oufaten, Morocco, we have Comura bultyncki, among the most famous of the Acastidae.  The photography was a pain, there were a lot of "ghost spines" I had to deal with.

 

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Trilobite of the week #127 is Nankinolithus sp, a Trinucleid of early Ordovician age from Mecessi, Morocco.  It has the usual features of that family -- short body, no eyes, high glabella, and a broad head shield filled with lines of pits.

 

 

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29 minutes ago, rew said:

Trilobite of the week #127 is Nankinolithus sp, a Trinucleid of early Ordovician age from Mecessi, Morocco.  It has the usual features of that family -- short body, no eyes, high glabella, and a broad head shield filled with lines of pits.

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This one was classified: Declivolithus titan

 

Fortey, R.A., Edgecombe, G.D. 2017

An Upper Ordovician (Katian) Trilobite Fauna from the Lower Ktaoua Formation, Morocco.

Czech Geological Survey, Bulletin of Geosciences, 92(3):311-322  PDF LINK

 

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This looks like another case where 90% of the fossil sellers have the wrong name for a relatively recently classified trilobite.

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Wow great collection of trilobites you have there ! B) :envy:

I like the looks of them (alien like) plus how early & successful they were. Though hearing many can be frauds or high restoration & me not knowing anything knowledgeable about them for species, restoration, rarity or not, prices, etc.... I tend to stay away from buying them & they're not that cheap :D 

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Trilobite #128 is Protolenus cf. termierelloides of late Atdabanian age from the Issafen Formation at Issafen, Morocco.  This is the earliest Ptychoparid trilobite in my collection.  The "cf." is because the species is defined from European specimens and this may or may not be the exact same species.

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2 hours ago, rew said:

Trilobite #128 is Protolenus cf. termierelloides of late Atdabanian age from the Issafen Formation at Issafen, Morocco.  This is the earliest Ptychoparid trilobite in my collection.  The "cf." is because the species is defined from European specimens and this may or may not be the exact same species.

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Geyer 1990 erected the new subgenus: Hupeolenus.  This one is: Protolenus (Hupeolenus) cf. termierelloides

The holotype of Protolenus (Hupeolenus) termierelloides is described from Morocco -- not a European species.

The FAD for P. (H.) termierelloides is the early Agdzian Stage -- the late Atdabanian Stage precedes it by ~2-3 myrs

 

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Geyer, G. 1990

Die Marokkanischen Ellipsocephalidae (Trilobita: Redlichiida).

[The Moroccan Ellipsocephalidae (Trilobita: Redlichiida).] 

Institut für Paläontologie der Universität Würzburg, Beringeria, 3:1-363  PDF LINK

 

Sundberg, F.A., Geyer, G., Kruse, P.D., McCollum, L.B., Pegel’, T.V., Żylińska, A., Zhuravlev, A.Yu. 2016

International Correlation of the Cambrian Series 2-3, Stages 4-5 Boundary Interval.

Memoirs of the Association of Australasian Palaeontologists, 49:83-124  PDF LINK

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Does the holotype come from the Issafen Formation, and if so, are parts of the Issafen Formation dated as being in the Agdzian Stage?

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11 hours ago, rew said:

Does the holotype come from the Issafen Formation, and if so, are parts of the Issafen Formation dated as being in the Agdzian Stage?

 

Geyer 1990 reports numerous localities including Issafen.  The holotype is from the Lemdad Syncline.

The chart from Sundberg et al. 2016 shows the temporal range for P. (H.) termierelloides (designated: Ht)

 

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Sundberg, F.A., Geyer, G., Kruse, P.D., McCollum, L.B., Pegel’, T.V., Żylińska, A., Zhuravlev, A.Yu. 2016

International Correlation of the Cambrian Series 2-3, Stages 4-5 Boundary Interval.

Memoirs of the Association of Australasian Palaeontologists, 49:83-124  PDF LINK

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