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Hoooooooooooorrrrrrrrrrrraaaaaaayyyyyyyyyyy!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Here we are at last, into Adam's Silurian. Thanks for looking. First up is the Lower Silurian or Llandovery and I begin with a problem. I posted this one incorrectly in Adam's Ordovician as it had got it's label muddled up with an Ordovician Favosites I had that has vanished in the move here, but is being replaced by kind forum member @Herb Anyway, this, I remember now I've found the correct label, is from the greenish Browgill Formation, part of the Stockdale Group from a cutting near Skelgill (Skelghyll) in Cumbria, Northern England. It seems to be a tabulate coral, but I can't find any listed for this location, only mentions of small, rare, rugose corals. It has the star shaped corallites of a Heliolitidid, but seems to be tightly packed together like a Favositidid. A couple of species of Palaeofavosites seem to be close and are a bit star-shaped,, but anyone know any better? @TqB@piranha hmm who else? The coral bit, an external mold, is a maximum of 3.5 cm across and each corallite up to 2 mm.
I am fortunate enough to have such a huge amount of Middle Devonian Givetian material that I thought it best to put the older Middle Devonian stage, the Eifelian, in its own thread. There are some spectacular fossils here as well though! I thought a good place to start would be in the Formosa Reef, which I believe is quite early Eifelian. This tabulate coral and stromatoporoid reef continues similar complexes found from the Middle Silurian, see my: https://www.thefossilforum.com/topic/84678-adams-silurian/page/3/ thread from page three onwards for details. All these Formosa Reef specimens come from a delightful gift from my good friend @Monica who is a tad busy with life at the moment but is fine and still thinking of the forum. This outcrop can be found on Route 12 near Formosa/Amherstburg, Bruce County, Ontario, Canada. This beautiful-looking specimen came to me with only a third of it revealed but I managed to get it this far after nine days of painful pin prepping. Monica found another one and posted it for ID here: https://www.thefossilforum.com/topic/105528-weird-circular-imprints-formosa-reef-lower-devonian/#comment-1172285 The specimen was identified by another Canny Canadian @Kane to be the little stromatoporoid sponge Syringostroma cylindricum. Hardly a reef-builder, but gorgeous nonetheless. It does have a little thickness to it, but not much. Beautiful! Pretty thin, actually. I love this Monica, thank you!
The thread http://www.thefossilforum.com/index.php?/topic/84678-adams-silurian/ was getting rather enormous, so I have decided to leave that one to deal with the Llandovery and Wenlock and put my specimens from the Late / Upper Silurian here, though I don't have a great deal of material from the Ludlow and Pridoli yet. However, I do still have some jolly nice specimens to show off here. Here are my other collection threads for the Cambrian and Ordovician ; http://www.thefossilforum.com/index.php?/topic/78887-adams-cambrian/&tab=comments#comment-832018 and : http://www.thefossilforum.com/index.php?/topic/78974-adams-ordovician/&tab=comments#comment-832912 In the mid 1980's, on the way home from one of my annual visits to the Hay-on-Wye second-hand bookshops, I managed to persuade my girlfriend at the time to take a bit of a detour and stop off at a roadcuttting just outside Aymestrey,, Herefordshire in the Welsh Borderlands. The rock here is the Aymestry (sic) Limestone Formation, part of the Upper Bringewood Beds and is Gorstian, Lower Ludlow in age, so about 426 mya and a little younger than the Much Wenlock Shale Formation. Many species of coral, trilobites and brachiopods found in the formation are the same as those found at Dudley, but the bed is noted for its massive numbers of the brachiopod Kirkidium knighti (was K. knightii),a lovely, large pentamerid. In fact, during my hour or so searching, I found almost nothing but this species, the only exception being a couple of Atrypa reticularis. The problem was that this limestone is thick and seriously hard, even the broken bits are generally huge, but I managed to obtain half a dozen reasonable specimens and about the same number of fragments. Over the years I have traded, given away or sold them, so that now I only have the best one left. Here is Kirkidium knighti : It's a shame the tip of the beak is broken off : I make index cards for all my fossils, this is the one I made for the specimens at the time, back in the mid 1980's : And today's version : There was a minor extinction between the Wenlock and the Ludlow, known as the Mulde event and it is often said to have primarily effected graptolites and conodonts, but it seems to me it had a massive impact on the bryozoan faunas of the time too. Gone are the varied stony stick and mound trepostomes that made up such an integral part of many faunas from the Middle Ordovician through to the Middle Silurian and even cystoporid groups such as the Constellariidae became extinct at this time. Trepostomes and cystoporids did survive until the end of the Triassic, but were never as important again, the bryozoan faunas would start to become dominated by fenestrids in the Devonian, though they reached their peak of diversity and distribution in the Carboniferous. I will look closely at my limited number of rocks, but I don't think I have a single Late Silurian bryozoan. I know our friend @Mainefossils studies the Late Silurian Leighton Formation in microscopic detail, but I can't recall him posting any bryozoans. Are there any, Asher, old chap? Interesting.
The Devonian period is known as "The Age of Fish", but could also be known as "The Age of Brachiopods." In the Early / Lower Devonian, brachiopods reached the height of their diversity towards its end in the Emsian. We see the ancestral groups occurring, lingulids, craniids, orthids, protorthids, pentamerids, rhynchonellids and strophomenids, as well as the later successful groups we have seen before such as atrypids, athyrids and orthotetids, plus the rise of spiriferids, spiriferinids and productids and the beginning of the terebratulids. By the end of the Devonian , several of these groups are extinct or severely reduced in importance and brachiopods never quite recover. Also, the Devonian is the last time we see trilobites with such variation, large sizes and numbers and orthocerids too are much more uncommon after the rise of the goniatites. The massive tabulate coral reefs also disappear after the Devonian. Fascinating period and I hope to share some of its wonders with you. Equally, a lot of this is rather new to me, so I would be very grateful for any assistance, corrections or further information on my specimens. Thank you. The Early Devonian epoch is split into three stages, so let's start with the first of those, the Lochkovian, that began about 419 mya and finished roughly 411 mya. I have been sent a nice selection of brachiopods from the Kalkberg Formation, Helderberg Group by the Mighty @Misha, mostly. But the kind gentleperson also sent me this fascinating little bryozoan hash : It is dominated by fenestellids, which is usually the case in the Devonian, but other orders sill occur. These ones, I think, are Fenestella, but there are so many species in the formation that I wont take a guess as to species : Not sure what this one is ;