Adam's Early / Lower Devonian

[Tidgy's Dad]

This one is Kozlowskiellina perlamellosa. 

Note the large endopunctae:

Kozlowskiellina tennesseensis also occurs in the Birdsong but is more elongated with closer spaced and more numerous costae. 

A microconchid : 

Near a crinoid holdfast on the anterior margin of the shell?

 

Edited October 4, 2022 by Tidgy's Dad

[Tidgy's Dad]

My favourite genus. 

Leptaena acuticuspidata.

This shows the trail very clearly:

Leptaena rhomboidalis also occurs in the Birdsong Shale but is larger, more rounded at the anterior and has a lot more rugae.

Leptaenisca concava has very faint rugae.  

 

[Tidgy's Dad]

My last brachiopod from the Birdsong Shale Member from Parsons, Tennessee is this quite beautiful pedicle valve of the orthotetid Xystostrophia woolworthana. 

This species was referred to the genera Schuchertella until Stigall's revision of Schuchertella and Schizophoria in 2005. 

Reading this also updated me on the brachiopod from the Glenerie Formation that I had down as Xystostrophia becraftenesis ( see near the top of the previous page) has now moved families and is Floweria becraftensis. The more I learn, the more I realize how little I know. 

It's worth noting that the genus Eoschuchertella seems to have been abandoned and all of the species that were assigned to it are now also Floweria or Xystostrophia. For example I have seen on TFF Eoschuchertella arctostriata a few times. This is now Floweria arctostriata.

Anyway, here is the quite rare Xystostrophia woolworthana :

 

 

 

 

 

[Tidgy's Dad]

There are usually epibionts on these large flat brachiopods and you can see in the photos above that this specimen of Xystostrophia woolworthana is no exception. 

Some colonies of Fistulipora sp.

And another cystoporate, Ceramopora parvicella. 

This species is distinguished by the way the apertures on the zooids being angles at nearly ninety degrees to the surface of the zooarium. They colonies are usually less than a centimetre in diameter. It is on the valve interior, near the hinge line suggesting it grew on the brachiopod postmortem. 

Thanks once again to the generous @Herb for these absolutely marvelous Birdsong Shale fossils in the last several posts. 

A delightful selection.

  

 

[Tidgy's Dad]

Moving away from the USA, the Lochkovian Stage and even brachiopods for a moment, here is a honeycomb coral, a favositid.

Crenulipora difformis from the Kess Kess Formation, Amerboh Group, Late Emsian Stage from just off the road between Erfoud and Hamar Laghdad, Draa-Tafilalet, Errachidia Province, Morocco.  I had a few of these, but have given the others away.

  

My second specimen : 

 

[Tidgy's Dad]

Popping over the straights of Gibraltar for a while, we of course return to brachiopods. 

I couldn't keep away for long.

My good friend Salvador @Paleorunner might be interested in this one and the next couple I'll be posting here. 

This one's not in the best condition, but the following two are much nicer. 

As with many spire bearing brachiopods this species was originally dumped into the bucket genus Spirifer. This one being S. subspeciosus. 

It was moved into the new genus Spinella by Talent 1956 as Spinella subspeciosa and was only very recently assigned to an even newer taxon Ferronia, so new  that the genus isn't listed in the latest Treatise main part, but is included in the Revision of Part H.

[Tidgy's Dad]

I've had a great deal of fun and it's been tremendously interesting following my fossil collection and the communities of life from the Precambrian through to this Lower Devonian section. 

The changes in some groups, such as the trilobites, has been extreme, the bryozoa have been a lot less conspicuous since the seeming mass extinction of many of the important trepostome groups, but the brachiopods haven't changed as much as I expected. 

After the Cambrian, when the 'inarticulates' and the orthids dominated along with several 'experimental' early groups, the brachiopod assemblages have been mostly ruled by the orthids and strophomenids with a pretty consistent presence of rhynchonellids and a few representatives of other orders. The rise of spiriferid and atrypid  numbers from the Wenlock onwards is noticeable but I was expecting them to be more dominant, along with the productids by the end of the Lower Devonian, but this has not been the case. Later in the period , I should think. 

One group that has surprised me is the increasing importance and variation in the Athyridida. Some groups resemble rhynchonellids, some look like terebratulids and other are similar in appearance to spiriferids and so on. Perhaps they are sometimes overlooked as they are mistaken for these other orders and maybe due to their previously being lumped in with the spiriferids, they are oft forgotten. 

Here is Quadriloba colletti, unique to the Colladilla Formation, La Vid Group from Colle, Leon, Spain. 

It's fascinating to me that while the spiriferids, like the Ferronia in the post above, are getting wider along the hinge line to incorporate ever longer spiralia, some of the athyrids are growing longer , away from a short hinge line  with more diagonal spiralia heading away from the beak and toward the anterior. 

 

 

[Tidgy's Dad]

Here's another beautiful example of the Athyrididae quadrilobate shape : Plicathyris esquerrai, also from the Coladilla Formation, but from the Bonar area of Leon, Spain Upper Emsian 

Before prep:

After prep: 

Pedicle valve;

Brachial valve ;

Anterior view :

Posterior view :

Lateral : 

Close ups :

 

Edited November 27, 2022 by Tidgy's Dad

[Misha]

Beautiful specimens! I really love these Coladilla Fm. Brachs

[Tidgy's Dad]

22 hours ago, Misha said:

Beautiful specimens! I really love these Coladilla Fm. Brachs

Yes, you have a very nice and interesting selection of them. 

I will have to get some more from the dealer if I can. 

 

Here are some better photos of the Ferronia subspeciosa shown a few posts above :

 

[Tidgy's Dad]

I don't have too many Palaeozoic bivalves, just the odd one or two from here and there, as well as a nice assortment from the Canadian Late Ordovician thanks to my good friend @Monica

I think bivalves weren't as successful as they later become and perhaps there is the thinness of the shells coupled with a larger size than brachiopods which might mean they break up more often? I think some shell fragments in some of my pieces are maybe bivalves and not brachs. Also it's collecting bias, of course, as I focus on brachiopods and brachs are often what people give or send me as well. 

But it's nice when I do have some. 

I found this piece of coquina near Erfoud towards the Hamar Laghdad and it has bits of at least four specimens in it. I don't think the top and bottom are valves from the same specimen. 

I couldn't find the bed from which this rock originated, it probably got washed down to the plains in a flash flood, but it's not seemingly water worn at all. 

Anyway, the genus is Panenka, which is mildly amusing as I'm currently watching some games of the football World Cup and some of you may know what a Panenka penalty is. 

Panenka is the most commonly found genus of bivalve in the early to Mid Devonian of this region and there are many species. But because it seems to have come from a bed packed with specimens of the species and also due to the large size and broad almost flat ribs, I'm going with it likely being P. hollardi from the basal Erbenoceras Beds, Amerboh Group, early Emsian, a layer of bivalves just before the ammonoids start to appear in this region. 

Look how big they are compared to some of my Lower Devonian brachiopods! 

 

[Paleorunner]

On 11/26/2022 at 7:55 PM, Tidgy's Dad said:

Here's another beautiful example of the Athyrididae quadrilobate shape : Plicathyris esquerrai, also from the Coladilla Formation, but from the Bonar area of Leon, Spain Upper Emsian 

Before prep:

After prep: 

Pedicle valve;

Brachial valve ;

Anterior view :

Posterior view :

Lateral : 

Close ups :

 

 

mmmm...... interesting brachiopods. 

[Tidgy's Dad]

On 12/5/2022 at 6:40 PM, Paleorunner said:

 

mmmm...... interesting brachiopods. 

I agree. There are several species unique to this formation. 

Our friend @Mishahas several. 

 

I have a few orthoconic nautiloids from across the Ordovician and Silurian, and I rather like them as they represent some of the predators of the time. And are attractive to look at. Usually there are only one or two species in a formation and they are relatively uncommon and even when larger numbers do occur, as in the Late Ordovician of the Etobokoke Creek Canada or Graf, Iowa, they're only one or two common species to be had.

The Moroccan strata of the Dra-Tafilalet region of South East Morocco is a bonkers exception. From the Late Silurian to the end of the Devonian there are a shed load of beds pretty much jam packed with dozens and dozens of cephalopod phragmocones of many orders.  ,

I have mentioned some of the Late Silurian ones elsewhere, so here are some of my Lower Devonian ones. Note that these don't include any of my specimens in matrix or any ammonoids. 

  

And as I've picked up some of these from shops and others have been found loose, I'm not even sure which beds they are from. And I know too little about this group of animals to make many guesses as to id. There are just so many possibilities and my pieces are fragmentary and don't show enough internal or external ribs or markings to be confident of ids. 

This one was obtained from a shop and was glued together with another specimen I will post later.; They may be from the same location, but I couldn't say for sure. 

It may not even be order Orthocerida as the orders Pseudorthocerida, Actinocerida, and Bactritida all have orthoconic species in some of these beds and the Oncocerida are sometimes only slightly curved. As the Oncocerida and Actinocerida are nautiloids but the Orthoceratoidea is now a separate subclass so Orthocerida and Pseudorthocerida are thus not nautiloids sensu stricto and Bactritoidea is also considered a subclass of Cephalopoda while the Actinocerida and Oncocerida are true nautiloids. 

So I can't even call these orthoconic nautiloids, the best I can do is straight shelled / orthoconic cephalopods. 

Though this one is most likely an orthocerid. 

Maybe. 

 

 

 

    

 

[Tidgy's Dad]

This is the one that was, rather bizarrely, glued to the specimen above. 

I'll have a guess at this one, even though it's only a fragment. 

I think this is Anthrophyllum vermiculare, which is interesting because it is a member of the same group as the Ordovician Lituites that I have. Some have these in as a suborder, the Lituitina of the Orthocerida, so they would be true orthocerids, but Kroger, 2008, has placed them back in the Lituitida, as a separate order.  

Notice the uneven size of the sections.

And the 'wormy' lines on the surface, possibly the reason for the specific name: 

 

 

[Tidgy's Dad]

I found this one myself, near Erfoud, but I don't know what it is, it seems to be preserved as an internal mold in weathered limestone. 

I expect the size, position and septal neck? in the opening would be a clue to id, but it's beyond me.

 

 

[Tidgy's Dad]

I do like this one, also from my collecting trip to Erfoud :

It's a bit worn and covered in hard limestone matrix, but I think it's the kind of specimen that many discerning forum members would much rather have in their collections than the polished half to death pieces you usually see.

 

You see these in considerable numbers just dumped together in a box at the back of some shops in Morocco. The tourists mostly buy the polished Temperoceras pieces.

They are invariably sold as Orthoceras and you also see them for sale online as Orthoceras, Temperoceras, Orthocycloceras or Michelinoceras. 

It's obviously not Orthoceras, as that's now a monospecific genus found only in  the Mid-Ordovician of Balto-Scandinavia.

You do occasionally see unpolished and matrix free specimens of Temperoceras ludense, but these are darker and marbled and not found near where I found this one. The genus does continue into the Devonian in the Erfoud area, but T. migrans is smaller and has thinner, / more closely spaced chambers. 

Both Orthocycloceras and Michelinoceras are true orthocerids, not just from the Order Orthocerida but from the family Orthoceratidae. 

Maybe Orthoccycloceras is usually, but not always a bit thinner and smaller, but there are a couple of different species that seem to vary a lot. Orthocycloceras fluminense seems to be Silurian and I'm pretty sure this fossil is Early Devonina, but it could be O. tafilaltense. 

Michelinoceras is a long-ranged taxon that lasted from the Ordovician to the Middle Triassic. Wow! The species Michelinoceras michlini is found in the Erfoud area and there is at least one undescribed species as well.  

Central siphuncle that unfortunately can't be seen at the anterior end:

And could these be crinoid holdfasts? You can see one in the photo above on the far left. 

Rakocinski (2011) suggested these can attach post mortem as they often appear on internal molds because the aragonite of cephalopod shells is dissolved during diagenesis. 

"Isolated cephalopod shells and internal molds likely served as benthic islands for various encrusters on a Devonian muddy sea-floor."

But the stem columnals are almost never found in these beds. 

   

 

[Tidgy's Dad]

This is my smallest one free of matrix. 

It's maybe just the tip of something much longer, but a lot of species are just small. 

It has very narrow chambers, a high angle of taper, a not quite central siphuncle with a very small opening. 

It's probably from the Pseudorthocerida, but there are others from the Orthocerida and even the Bactritida which look much like this. 

 

[Tidgy's Dad]

This is a nice chunky piece that is only a very small part of what would have been quite a big creature. And they got much bigger than this in the region back in the Lower Devonian. 

Many  of these medium to large orthocones found near to Erfoud are actinocerids such as the common Deiroceras hollardi, while others are true orthocerids like Tibichanoceras which could get really enormous. 

There's not really enough of this specimen, which I found near Erfoud and is probably Pragian, to be able to guess and I have little with which to compare. 

 

 

[Tidgy's Dad]

I thought this was a horn coral at first. 

The I thought it might be a bent orthocone, but I know think it's some sort of cyrtocone. 

The chambers are comparatively long, so I thought it was Pseudendoplectoceras sp. but the siphuncle seems to be slightly wrong for that, Pseudendoplectoceras should have the siphuncle positioned slightly towards the concave side and this specimen seems to have it located slightly toward the convex side. 

 

[Tidgy's Dad]

This is a rather rolled roller from the hamada between Erfoud and Jebel Boutchafrane and Hamar Laghdad. 

It's poorly preserved and the eyes are mostly gone making id pretty much impossible, but I found it myself so I'm rather fond of the little fellow. 

The most common rollers preserved around the location are washed down from the hills and mountains and are Early Devonian phacopids, usually Pragian species, such as Reedops cephalotes hamlagdadianus.  

[Tidgy's Dad]

This is a pretty decent sized specimen of Paralejurus from the Pragian, Lower Devonian south of Morocco.  Prone it would probably measure about 3 inches. 

I purchased this one for a few dollars but the vendor didn't know the locality, but it would appear to be P. hamlagdadicus. 

Or perhaps P. spatuliformis.. 

The prep's not perfect, but I think it's a beauty.

The right eye is a bit damaged.

The left side is much nicer.

Ventral anterior showing lovely terraces : 

Beautiful and tiny lenses in the eye : 

 

Dorsal anterior detail: 

The other eye is a bit squished :

 

Pygidium detail : 

A weird thing in the matrix; 3.5 mm wide :

 

 

 

 

[Tidgy's Dad]

A nice little Gerastos tuberculatus marocensis. 1.7 cm long. 

This one came from a table with dozens of very similar sized specimens. There were also boxes of them under the table. 

No locality was specified, but the preservation, prepping (I've done a little myself) and my scant knowledge lead me to believe that they may be from Jbel Gara el Zguilma, Foum Zguid, Tata, Souss-Massa, Morocco. Probably from the Timrhanrhart Formation and Upper Emsian in age. 

They are so common at this location, the local Berbers call them "Izi" which means flies in their Amazigh tongue. 

Edited February 22, 2023 by Tidgy's Dad

[Tidgy's Dad]

Another Gerasos tuberculatus marocensis. 

This one is considerably bigger, and may be from a different location to the specimen above.  

Judging from the size, preservation and other species found with it's just a bigger example of the species above. 

Others that I haven't prepped, probably from the same Late Emsian, Early Devonian fauna.

I think Hollardops, Coltraneia and Cornuproteus ? 

These look like they could be from the Upper Emsian of the Timrhanrhart Formation, but maybe a different location.

Rock colour and the very rough prep seems to be different. I think that these are examples of common trilobites that are used as prep practice for beginners so you can pick these up very cheaply though they're often a bit mangled. 

Edited March 15, 2023 by Tidgy's Dad

[Bobby Rico]

Nice mate to catch up on this thread. I really like the little collection Monica sent you. 

[Tidgy's Dad]

On 3/14/2023 at 10:41 AM, Bobby Rico said:

Nice mate to catch up on this thread. I really like the little collection Monica sent you. 

I think my post there was a little confusing. The Monica bivalves are under my "Adam's Ordovician" thread. 

Those shown above are my own collections from Morocco and Spain as well as items sent to my by my good friends the generous @Paleorunner and USA brachiopods from the kindly @Herb.

I'm' glad that you enjoyed catching up on my little thread.