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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!

As there are some polished fossil-rock specimens from this formation in the Christmas auction, I would like to present some background info with (mostly) some field photographs, so I have put this in “Fossil Hunting Trips”. The Palaeozoic of Graz is a thrust sheet within the Eastern Alps, composed of Silurian to Pennsylvanian sediments. It consists of three separate nappes, the most fossiliferous formation is the Plabutsch-formation within the Rannach nappe. This Devonian formation is of Eifelian age (ca. 395 Ma), about 100 m thick and mostly made up of a very dark, gray-blueish to black, fine-grained, thickly bedded limestone. Superficially, it weathers to a medium to light grey color. Geological map of Styria with the Palaeozoic of Graz situated north of Graz. Stratigraphic column of the Rannach nappe of the Palaeozoic of Graz, Plabutsch-formation is Nr. 4. From Hubmann & Gross, 2015. Thicknesses of formations are not to scale! The Plabutsch-formation crops out at various places to the west and north of Graz and more than 100 fossil sites are known within this formation. The most abundant fossils are corals, brachiopods, stromatoporids and crinoid fragments. Other fossils like gastropods, bivalves or trilo-bits are very rare. In a paper from 1975, about 50 coral species are listed, but less than 10 are abundant: Tabulata: Favosites styriacus Penecke, 1894 Pachycanalicula barrandei (Penecke, 1887) Thamnopora boloniensis (Gosselet, 1877) Thamnopora reticulata (Blainville, 1830) Striatiopora? suessi Penecke, 1894 Rugosa: Thamnophyllum stachei Penecke, 1894 Zelophyllia cornuvaccinum (Penecke, 1894) Do you feel that there is something strange with this list? Yes, it is! Most species have their type locality within this formation and were first described by Penecke, except T. boloniensis (T. reticulata was also erected by Penecke as Pachypora orthostachys and later synonymized with an earlier described species). In my opinion, this does not reflect a high degree of endemism, but an urgent need for revision… The most abundant fossil is Favosites styriacus, which can form massive colonies up to 0.5 m in size. Here is an example from Hohe Rannach Mt. (1018 m) north of Graz, photo 05/26/2018, Col-Nr. 4093, length of pocket knife is 9 cm: As most fossils in this formation, it was found in scree and float in a wooded area. Nr. 4093 is waiting near the pocket knife toward the lower right corner… Another Favosites styriacus, north of Fürstenstand Mt. (754 m), northwest of Graz, photo 10/30/2015, not in collection. Tabulae are very well visible, weathering is usually your friend there!