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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 ;

I thinking I might have put something out on these before, but it might have been via PM and mostly on the trilo-bit pieces. I am looking to see if anyone has a possible ID on the shells. I believe that this material might be Devonian in age. I picked this material up at an ESCONI members Garage sale a couple of years ago. There are a number of pieces and it was supposed to have come from an old collection. Any help would be appreciated. Some other piece’s including trilo-bits.

Image of a Reconstruction of the Caiman Mourasuchus and Prehistoric Dolphins in Miocene Venezuela by Julio Lacerda Image Source: https://www.facebook.com/art.julio.lacerda/photos/mourasuchus-was-a-very-large-caiman-with-a-distinctly-flat-head-and-numerous-sma/2971939362916938/?_rdr In the Northern and Central Basins of Miocene South America between 23-5.3 Million Years ago, there was a giant system of lakes known as Lake Pebas. Fed by rivers directly connected to South America’s Caribbean Atlantic Coast, this lake system at its largest covered an area slightly bigger than 1,000,000 square kilometers (km2) in what is today part of Brazil, Colombia, Peru, Venezuela, and Bolivia. The lake system was home to a variety of life including a vast diversity of dugongs, fish, dolphins, land mammals, and Crocodilians (when I say crocodilians, I mean the general group within the archosaur family that includes Crocodiles, Gavialoids, and Caimans). Image of Reconstruction of Lake Pebas Image Source: https://www.researchgate.net/figure/Palaeogeographical-model-of-northwestern-South-America-during-the-Middle-Miocene-some-14_fig6_254893768 While Crocodilian diversity decreased globally after the warm Paleocene and Eocene eras, emergence of the lake pebas system paved the way for an explosion in diversity for these semi-aquatic reptiles in Northern South America. This is best demonstrated by the vast and diverse Miocene crocodilian fossils found in the Urumaco Formation and Pebas Formation. https://www.sciencedirect.com/science/article/abs/pii/S0895981118303699 https://igeo.ufrj.br/inc/isc/3/3_87-Souza_Filho_etal_2020_Melanosuchus_latrubessei.pdf https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4375856/ These heyday for South American crocodilians saw the emergence of some of the largest aquatic crocodilians currently known on Earth since the Creteaceous and Paleocene eras, including Giant Caimans Purassaurus and Mourasuchus amazonensis. Image of Reconstructions of the sizes compared to an adult Human of several notable Crocodilians from Lake Pebas by Armin Reindl Image Source: https://www.deviantart.com/arminreindl/art/Crocodilians-of-the-Pebas-Megawetlands-900353328 The Lake Pebas system would persist up until the formation of the Andes Mountains during the Late Miocene. This decreased the size of the Pebas lake system and ultimately help give rise to one of the World’s most spectacular river systems, the Amazon. Crocodilian diversity in the region decreased as well and now only a few crocodilian genera inhabit South America currently. Lake Pebas is also the primary reason why the Amazon River system is home to freshwater stingrays, freshwater manatees, and freshwater dolphins. When Lake Pebas started to decrease in size, those creatures successfully adapted to the more freshwater environments of the Amazon River. Here's a list of all the currently known crocodilian genera and species that lived in the Miocene Lake Pebas system. If I forget any examples, please let me know and I'll add the examples to the list promptly. Unnamed Paleosuchus sp. (Alligatoridae) (Miocene, 16.0-11.6 Million Years ago) (grew up to 1.2-1.4 meters (3.9-4.6 feet) in length) Kuttanacaiman (Alligatoridae) (Miocene, 15.97-11.6 Million Years ago) (grew up to 1.71-1.88 meters (5.62-6.20 feet) in length) Gnatusuchus (Alligatoridae) (Miocene, 11.6-5.3 Million Years ago) (grew up to 1.49-1.67 meters (4.89-5.50 feet) in length) Gryposuchus (Gavialidae) (Miocene, 16.3-5.3 Million Years ago) (grew up to 10 meters (33 feet) in length) (five species currently known, four species lived in the adjacent rivers of and in Lake Pebas itself) G. jessei (Miocene, 11.6-7.2 Million years ago) G. pachakamue (Miocene, 11.6-7.2 Million Years ago) G. croizati (Miocene, 11.6-5.3 Million Years ago) G. colombianus (Miocene, 16.3-11.8 Million Years ago) (Note: One unnamed Gryposuchus sp. May have survived up to the Pleistocene, 2.6-0.012 Million Years ago in what is now Paricao, Brazil) http://www.fossilworks.org/cgi-bin/bridge.pl?a=collectionSearch&taxon_no=38417&max_interval=Quaternary&country=Brazil&is_real_user=1&basic=yes&type=view&match_subgenera=1 Hesperogavialis (Gavialidae) (Miocene, 11.6-7.2 Million Years ago) (grew up to 10 meters (33 feet) in length) Brasilosuchus (Gavialidae) (Miocene, 9 Million Years ago) (grew up to 3.6-3.9 meters (11.9-12.9 feet) in length) Charactosuchus (Crocodylidae) (Eocene-Miocene, 48.6-7.2 Million Years ago) (grew up to 3.6-3.9 meters (11.9-12.9 feet) in length) (three species currently known, two species lived in the adjacent rivers of and in Lake Pebas itself) C. fieldsi (13.8-7.2 Million Years ago) C. sansoai (11.6-7.2 Million Years ago) Mourasuchus (Alligatoridae) (15.9-5.3 Million Years ago) (Largest Mourasuchus sp. Grew up to 4.7-5.9 meters (15.4-19.3 feet) in length) (five species currently known (including one unnamed Mourasuchus sp. From Bolivia), four species lived in the adjacent rivers of and in Lake Pebas itself) M. amazonensis (Miocene, 9.0-6.8 Million Years ago) M. pattersoni (Miocene, 9.0-6.8 Million Years ago) M. atopus (Miocene, 15.9-11.8 Million Years ago) M. arendsi (Miocene, 11.6-5.3 Million Years ago) Unnamed Caiman sp. (Based on Specimen UCMP 39978) (Alligatoridae) (Miocene, 15.97 Million Years ago) (size: NA) Caiman wannlangstoni (Alligatoridae) (Miocene, 13.8-5.3 Million Years ago) (grew up to 1.7-1.9 meters (5.5-6.2 feet) in length) Caiman brevirostris (Alligatoridae) (Miocene, 11.6-7.2 Million Years ago) (grew up to 1.7-1.9 meters (5.5-6.2 feet) in length) Broad-snouted caiman (Caiman latirostris) (Miocene-Present, 9.0-0.0 Million Years ago) (grows up to 2.0-3.5 meters (6.5-11.4 feet) in length) (still extant in the present) Acresuchus (Alligatoridae) (Miocene, 9.0-7.2 Million Years ago) (grew up to 3.4 meters (11.2 feet) in length) Purussaurus (Alligatoridae) (Miocene, 16.3-5.3 Million Years ago) (grew up to 9.2-10.9 meters ( 30.2-35.7 feet) in length) (four species currently known (including one unnamed Purussaurus sp. From Panama), three species lived in the adjacent rivers of and in Lake Pebas itself) P. brasiliensis (Miocene, 9.0-7.2 Million Years ago) P. neivensis (Miocene, 13.8-11.8 Million Years ago) P. mirandai (Miocene, 11.6-5.3 Million Years ago) Melanosuchus latrubessei (Alligatoridae) (Miocene, 10.89 Million Years ago) (grew up to 4 meters (13.1 feet) in length) Globidentosuchus (Alligatoridae) (Miocene, 11.6-6.8 Million Years ago) (grew up to 1.72 meters (5.6 feet) in length) Hope you all find this helpful!!!

Hi all- I am doing some cataloging of fossils here at the office. This came is as a donation a while back and I need help IDing it. They were purchased with no info. These trilobites were in a nodule of sorts. I have seen this sort of preservation from Morocco and Bolivia and maybe Peru. Can anyone help me with genus and country of origin? The photo with my hand in it shows the outside of the nodule, if that helps. Thanks JP

This is a fossil bone from corocoro bolivia, any coments please, regards

I have recently added this piece to my collection. Was sold to me as a Sedimentary Stromatolite from Bolivia. No further info given. I have looked online and in my book and can't match it to anything. Is this a genuine Stromotolite? - it wasn't too expensive, and it's quite attractive either way. Photo of both sides. Roughly 11cm square

Hello everyone! As you can see, I'm new to TFF and this will be my first substantive post, so if you have time I would appreciate any help in understanding what this fossil actually is so I can learn more about it. I've tried to follow the guidelines for posting as closely as possible (with limited information regarding collection) but if I have made some mistakes I apologize up front. My wife purchased this fish fossil for me in either La Paz or Cochabamba Bolivia in 1996 at a market. She didn't get any further information regarding where it was collected or what it is. She also purchased another fossil that I'll post later. I do not believe this fossil was actually collected in Bolivia, as it looks like vinctifer comptoni, which I have read is fairly common in the Santana formation in Brazil. But, I am an admitted neophyte and that is simply a guess. What do the experts think this is? I would like to learn more about the fossil and the possible collection area and age, and having an actual identification would certainly help in that! Thanks for reading and I appreciate any information. Regards.

https://phys.org/news/2018-06-ancient-mammals-bolivia.html https://www.eurekalert.org/pub_releases/2018-06/cwru-usa062718.php

I found someone selling a few Bolivian trilobites in ironstone nodules and I really like this one (above). Most of the others have an oxide coating (example below) and this one does look very slightly yellowish. Will it (or other fossils in ironstone like those from Mazon Creek) be stable long term? I don't really want to buy it if it will just rust away.

Could anyone show me how to tell Eldredgeia venustus from Eldredgeia eocryphaeus in these specimens?

I lived several years in Bolivia, doing botany, ethnobotany, agronomy and agriculture. On december 28th, 1998, travelling in my car with my family around Lake Titicaca, I took these pictures of magnificent fossiliferous marny strata on the side of the road between the strait of Tiquina https://en.wikipedia.org/wiki/Strait_of_Tiquina and Copacabana (Tiquina is between Huarina on the map and Copacabana), on the bolivian southern side of the lake. Geologically, this area seems to belong to Devonian. What do you think about this ? As being not paleontologist, it would interest me. Thanks in advance for your remarks. * I remember that In the 1990' and 2000', one could purchase in the streets of La Paz, as I saw it many times, fake Trilobits made of black terracota by Aymara people (traders in the soul and skilful crafts men) very, very nice and accurates and certainly made by moulding. This kind of geological site was perhaps a source o inspiration for them...

Hi, I just signed in on fossilforum to see whether anybody is able to help me ID the fossil in the picture. Although I´ve read the guidelines on posting pics I'm afraid I can't offer any better pictures since the fossil in question is not in my posession and I was only able to take the picture attached. I did some checking on the internet, and my (very not expert) guess is it might be the upper jaw (part of skull) of some kind of ground sloth. The fossil was dragged up from the Orthon River in the northern Amazon of Bolivia, while dragging for gold. Apparently at the time they also found other parts of the animal including ribs, but it would be very difficult to retrieve any of this. I'd appreciate any suggestions on what this might be. Vincent