Adam's Early / Lower Devonian

[Tidgy's Dad]

This is the specimen shown top right in the photo at the end of the last post though I've tidied it up a tad. I think it was used for prep practice because the shiny black shell is missing from the cephalon and the eyes are missing, therefore making it of limited commercial value.

From the Upper Emsian / Lower Eifelian, I think that it's Cornuproetus sp. These are often sold as C. cornutus, but I'm not sure that that species is valid in Morocco and I can't check my papers as my computer is in for repair..

Maybe Cornuproetus djelmensis?

There are several other members of the family Tropidocoryphidae about as well.

You can see why preppers scratch the surrounding matrix for contrast.

 

Edited March 29, 2023 by Tidgy's Dad

[Tidgy's Dad]

I've been hurting my fingers and gone through about 50 board pins prepping the next trilobites. Still haven't finished but relief is at hand. For hand. 

 

I have always made a jolly good effort to identify the bryozoans in my collection and have a large number of species from the Late Ordovician to the Middle Silurian. Bryozoan forests of chunky, lovely specimens. And then it pretty much stops; allmost nothing for the Late Silurian and Lower Devonian, just a few fragments of fenestrid and a cyclostome and cystoporid or two. So, it was of no surprise when I discovered recently that the trepostomes and cryptostomes had suffered major extinctions at the snd of the Wenlock ( Middle Silurian) from which they never really recovered. 

Aware of my searching, the magnificent @Misha recently sent me another parcel and amongst the many much loved brachiopods was a small piece of bryozoan smash hash to add to the fenestrid piece he sent me on a previous occasion. (shown on page one of this thread.) 

The whole piece is about 5 cm long and 3.5 cm wide but contains lots of broken up bryozoan bits, possibly smashed to bits in a storm before being buried in the soft mud that makes up these shale bands in between the limestome layers of the Kalkberg Formation of Rickard Hill Road, Schoharie, New York, USA. 

 

And look! Bottom left is a treposome, my first from the Early Devonian! This is the earliest stage of the Devonian, the Lochkovian, so very exciting foe me. 

Out with the pins! 

I think this might be Monotrypella arbuscula, but any alternative suggestions are most welcome. 

1.8 cm long and about 3mm at its widest. 

I will try to remove more of the nasty matrix from between the two branches when my fingers have recovered a tad.

Edited May 22, 2023 by Tidgy's Dad

[Tidgy's Dad]

Actually, I may have already had an Early Devonian trepostome from Rickard Hill Road that I found in that fenestellid hash mentioned above. 

And I have just found some smaller but similar pieces in the new hash : 

The bigger bryozoan with the diamond shapes shown below could be a fenestrid, but seems to be curved into a possibly more ramose form. So it may be a fragment of a species of Ptilodictya if these are zooecia that are full of matrix rather than the fenestrid 'windows'. 

The chunkier bit with two parallel lines and connecting bits is a fragment of a fenestrid. 

These trepostomes have well spaced, oval zooecia with raised rims, so I think they may be one or more of the species of Callotrypa that are found at Schoharie. 

Edited May 22, 2023 by Tidgy's Dad

[doushantuo]

aweome

[Bobby Rico]

I love the macro photos they look a otherworldly landscape . 

all good stuff. Bobby 

[Bobby Rico]

On 10/7/2022 at 12:46 AM, Tidgy's Dad said:

Leptaena acuticuspidata.

Wow that’s beautiful. 

[Tidgy's Dad]

32 minutes ago, Bobby Rico said:

I love the macro photos they look a otherworldly landscape . 

all good stuff. Bobby 

Thank you, my friend, I entirely agree, a view into an ancient, alien world. 

And here's some more fenestrid bits from the same piece of Kalkberg limestone bryozoa hash shown above.

Only tiny fragments, not going to guess at species, but I think pretty, nonetheless. 

[Tidgy's Dad]

4 hours ago, doushantuo said:

aweome

Thanks, Ben, I agree. 

But this one is even more spectacular. 

This is a fenestrid / fenesrate but not a fenestellid. Not a member of the family Fenestellidae but the family Acanthocladidae, meaning spinose. 

Just a central stem with side spikes not connected to another stem. 

I'm fairly certain of this id and it's great, as the genus is well known from the Early Carboniferous, but very rare before this. 

Two examples of the spiny bryozoan Ichthyorachis nereis, a great generic name that means 'fish vertebral column'. Excellent. 

The first one is 3mm long, the second only about 2, they're less than a millimetre wide and the side spikes are ridiculously thin. 

WOW! 

There are also a few lumpy bits, like the one shown below, 3mm in circumference, which could be a bryozoan such as Leioclema ponderosa, or a small sponge? 

 

Edited May 22, 2023 by Tidgy's Dad

[Tidgy's Dad]

I took this photo for a number of reasons : 

1) To show off the 3D printed scale cube that the Mighty @Misha included with the fossils. There's a white one as well which I'm sure will make an appearance on this thread before long. Unfortunately, wifey's camera phone thingy seems to have focussed on the cube and not the fossils.  A bad workman always blames his tools. Still, you get the idea of the sizes which was the point, I suppose. 

2) To show a new brachiopod (centre) compared to one of the ones from a previous parcel which I have as probable Mesistella laevis. (right) 

3) And on the left a bryozoan which I initially thought was a massive form but then realized was an encruster on a brachiopod that I thought might be a Meristella due to the seeming size and shape. 

×

The bryozoan is the encruster Paleschara incrustans. Until quite recently the family Palescharidae was tentatively listed as a cryptostome family of uncertain suborder, but recently it has been placed in the Fenestrata eg. Sepkoski 2002. So this formation contains multiple fenestrates; species of Fenestella, Polypora, the spiky Ichthyorachis shown in the last post and now an incruster. There are others listed, too. Fenestates reach their peak in the Carboniferous, but you cam already see their importance and range of forms here in the Early Devonian. 

Below you can see the broken shell of the brachiopod and that this encrusting bryozoan is very thin, which is correct for this species. 

A sort of hexagonal, honeycomb pattern, the zooecia are right nect to each other, separated by thin walls: 

And here we see part of the host brachiopod, confirming it's not Meristella,  as I had thought, but possibly a spiriferid. Paleschara incrustans can be found growing on various brachiopods, corals and even other bryozoa, but its favourite host seems to be the spiriferid Megakozlowskiellina perlamellosa. I posted this brachiopod earlier in this thread.

At the angles, the walls of the zooecia are sometimes raised higher, but not enough to be called spines. 

Quite a thin layer covering the brachiopod shell : 

 

Edited May 24, 2023 by Tidgy's Dad

[doushantuo]

because that's how I roll, I feel i have to point out the possibility that the epizoan figured by Adam could ALSO  be a Hyostragulum,a coral which often occurs as

an epizoan in conjunction with trepostomes,or conceivably,cryptostomes.

Given the mophology of the coral,a chequered taxonomic past is a distinct possibility

Edited May 24, 2023 by doushantuo

[Tidgy's Dad]

11 hours ago, doushantuo said:

because that's how I roll, I feel i have to point out the possibility that the epizoan figured by Adam could ALSO  be a Hyostragulum,a coral which often occurs as

an epizoan in conjunction with trepostomes,or conceivably,cryptostomes.

I don't think so, Ben

Hyostrangulum seems to be an epibiont almost exclusively on hyoliths, with rare occurences on gastropods and nautiloids. I find no reference to the genus growing over brachiopods. 

It's also a European genus, there's no mention of it in the faunal lists I have for the Kalksberg or indeed New York or the USA, as far as I can see. 

And the corallites seem to have thicker walls and are more ovoid in shape than the zooecia in my specimen. 

[doushantuo]

I'm somewhat partial to your arguments,particularly the biogeographical one,although I am very prone to taking paleozoic palinspastic reconstructions into

account when practicing my brand of taxonomy

BTw ,im looking at

"Epizoic bryozoans and corals as indicators of life and post-mortem orientations of the Devonian brachiopod Meristella"(Lethaia /1995)
CLIFFORD A. CUFFEY, ALBERT J. ROBB, JOHN T. LEMBCKE, ROGER J. CUFFEY

right now,

"Three bryozoans, Cyphotrypa corrugata, Fistuliporella maynardi and Leioclema pulchellum, and one coral, Favosites conicus, are considered. "

 

Edited May 25, 2023 by doushantuo

[Tidgy's Dad]

30 minutes ago, doushantuo said:

"Epizoic bryozoans and corals as indicators of life and post-mortem orientations of the Devonian brachiopod Meristella"(Lethaia /1995)
CLIFFORD A. CUFFEY, ALBERT J. ROBB, JOHN T. LEMBCKE, ROGER J. CUFFEY

right now,

"Three bryozoans, Cyphotrypa corrugata, Fistuliporella maynardi and Leioclema pulchellum, and one coral, Favosites conicus, are considered. "

 

And what has this got to do with the price of bananas? 

[doushantuo]

or even avocado's?

[Tidgy's Dad]

Here's a Meristella. 

Meristella atoka, the subject of the paper mentioned above, is found in the Birdsong Formation of Tennessee and the Harrigan and Bois d'Arc Formations of Oklahoma, but the New York species are different. There are about five species in the Kalkberg at Schoharie and this one seems a little different to the three specimens I posted on page one of this thread, which I belive could possibly be M. laevis. 

This specimen seems smaller, less inflated or curved and has a more pointed posterior. It also has a shallow sulcus towars the anterior. maybe M. arcuata, but with the commissure and most of the brachial valve missing, it's really rather a guess. So, Meristella sp. 

The sulcus is clearer in the photo below.

Nice pedicle opening.

 

 

Edited May 26, 2023 by Tidgy's Dad

[doushantuo]

Nice!

 

Adam,can you still edit the post and change "suclus"

[Tidgy's Dad]

I posted a possible Anastrophia verneuili from the Catskills near the top of page three of this thread. 

I'm slightly more confident that this specimen from Rickard Hill Road, Schoharie is one. 

It might be a rhuchonellid, but I see no signs of a fold or sulcus and the commissure is mostly covered in matrix. 

It's really great to have these pentamerids, as the whole suborder to which Anastrophia belongs became extinct at the end of the Early Devonian and the entire Order Pentamerida were gone by the end of the period, seemingly in part replaced by the new Order Terebratulida, often a similar size and shape and occupying many of the same ecological niches. 

Edited May 29, 2023 by Tidgy's Dad

[Tidgy's Dad]

This one is only 8 mm wide. 

I don't think that it is a smaller species of rhynchonellid, the shape and ribbing seem wrong, but I believe it to be a juvenile Machaeraria formosa. 

I posted an adult specimen near the bottom of the first page of this thread. 

The fold is there, but not showing clearly, below it is a little but clearer : 

 

 

[Tidgy's Dad]

I posted some Uncinulus from the Kalksberg Formation of Rickard Hill Road, Schoharie, back on the first page of this thred and remarked on how odd it was that they were all single valves or had been broken in half and this one seems to be much the same, though the other valve may have just been glooped in sediment and partially destroyed. 

It's rather a nice one, though., and clearly a different species. 

I think this is the brachial valve of Uncinulus nucleolatus. 

Notice the flattish beak, the sudden, almost 180 degree curve creating a dome shape, and then a long amost flat anterior edge. It also has a very low fold with broad, flattened costae that have a shallow groove running through each one. 

The black cube is an inch square. 

 

 

[Tidgy's Dad]

This is a wonderful piece! 

Still from Rickard Hill Road, Schoharie, Kalkberg Fornation, Lochkovian, Early Devonian.

A hash with three nice brachiopods on one side;

And one on the other, along with a my first horn coral from this location or age. 

There are also lots of disarticulated crinoid ossicles, also the first I have from this location, but no bryozoa. Not even fragments. This is interesting as I have a little fenestellid hash from this area and another hash with lots of fragments from several small species of Fenestrida and other orders. Did the bryozoans live in a different ecolocical niche than the brachiopods, corals and crinoids? 

 

 

Though I may have a possible partial solution to my "Bryozoan Gap", the extinctions of the bryozoans at the end of the Wenlock. 

It seems that during the Early and Middle Silurian there were different bryozoan faunal provinces separated by the Iapetus Ocean. 

So, the North Americans had one set of mostly different species, the Welsh/ English another and the Balto Scandinavia a third. This matches with the very different Wenlock species I have found from material in those three different regions. There was a fourth bryozoan faunal province in what is now Mongolia, but I haven't had the opportunity to study the species from there. 

It's also interesting that the coral and brachiopod species are very similar in the different areas and this was apparently due to how far the free-swimming larvae of the different groups could travel. 

During the Wenlock, the Iapetus Ocean started to close and this resulted in the merging of the different zones, except the Mongolian one and by the end of the Wenlock the others had become one faunal province and a battle for survival occurred as the different species came into competition with each other. A real survival of the fittest event. 

But this would explain a reduction in species but not the almost total extinction of the two major groups. 

It would appear that a massive change in environmental conditions occurred due to the convergence of the continents which may help explain it, but why did it effect bryozoans so much more than other groups? 

And what about my Bryozoan Gap? 

I hypothesize that the extinctions were so heavy that there was little base to recover from and until conditions changed, the fenestrates took a longer time than usual to diversify and fill the empty ecological niches.

Edited July 26, 2023 by Tidgy's Dad

[Bobby Rico]

14 hours ago, Tidgy's Dad said:

A hash with three nice brachiopods on one side;

This is cracking hash plate . I enjoyed reading your hypothesis very interesting. 

[Tidgy's Dad]

2 hours ago, Bobby Rico said:

This is cracking hash plate . I enjoyed reading your hypothesis very interesting. 

Thanks. 

I'm very intrigued to see when bryozoans start to appear in large numbers and large sizes again. At least in my collection. 

For now, here's more on that horn coral from the hash above.

These are often listed as Streptelasma (Enterolasma) strictum, and sometimes as Enterolasma strictum. I think the latter is correct as Enterolasma seems to have been raised to genus level and it now even has its own subfamily, the Enterolasmatinae, but still in the family Streptelasmatidae. Nice to see this ancient family still going strong. 

E. strictum seems to be fairly common in the Kalkberg Formation, but often has the calyx, where the structure is hollow, crushed as in my specimen. 

This is the other side of the rock. You can see a part of the other side of the coral top centre of the rock. I didn't prep it out any further as I think it would disintegrate because of the crushed calyx.

Lots of crinoid ossicles and maybe ostracods? Are ostracods found in the Kalkberg? I'll have to have a look. 

The crushed calyx. A few septa ends are just about visible in places but don't show up well in these photos. 

 

Edited July 26, 2023 by Tidgy's Dad

[Bobby Rico]

1 hour ago, Tidgy's Dad said:

here's more on that horn coral from the hash above

That hash plate giving out the goods, nice photos BTW .

[Tidgy's Dad]

20 hours ago, Bobby Rico said:

That hash plate giving out the goods, nice photos BTW .

It is indeed.

Here's the big brachiopod, Discomyorthis oblata. Lots of these from here and elsewhere on this thread. 

 

[Tidgy's Dad]

And another orthid, really not sure, but maybe Tyersella perelegans? 

Edited July 30, 2023 by Tidgy's Dad