Show Us Your Fossils Challenge Mode: Ordered By Geologic Time Period!

[siteseer]

Here's a jaw section with teeth identified as Captorhinus from the Early Permian Arroyo Formation, Comanche County, Oklahoma.  It's 28mm long and belongs to a reptile genus known from not just Oklahoma but also Brazil, Europe, and India.  It lived at a time when the continents were almost reunited into one supercontinent so it was a lot easier to walk the earth back then even if you were a small land animal.

 

I've seen people assemble skeletons of this genus from isolated, unassociated elements which gives you an idea of how common this animal can be at some sites.  Of course, it's no easy getting the sizes right.  I've seen a couple of pretty good looking Frankensteins.

 

 

[TheInvertebrateGuy]

A branching Archaeocyatha from the Cambrian, with visible osculums. I found this at the shores of Lake Michigan near a quarry. There are also other Archaeocyathids all around the rock in the shape of small ovals.

 

 

I know I’m a bit late on this topic but I just want to share a find of mine.

[siteseer]

On 6/29/2022 at 2:07 PM, ziggycardon said:

Morganucodon watsoni teeth found in the Pant Quarry, (Fissure Fills), Near Bridgend, South Glamorgan, Wales, UK (Triassic, Rhaetian, 205 mya)

 

I don't want to let your Morganucodon teeth go without further note.  Great specimens, by the way.  Morganucodon is an interesting animal because it's considered the earliest known mammal genus by many paleontologists while others have concluded it belongs to a group closely-related to early mammals.  Either way, it's a funky beast.  Unlike most Mesozoic mammals/mammal-like forms, other parts of Morganucodon’s skeleton are known and there appears to be evidence it had fur and the females produced milk for their offspring which would qualify it as a mammal.  It might have laid eggs.

 

This is the kind of fossil many mammal collectors don’t think about because they don’t know it’s occasionally commercially-available.  We think about early mammals as horses the size of a housecat or maybe a whale with feet from the Eocene but the first two-thirds of mammal evolution took place before the dinosaurs died out and Morganucodon lived all the way back to the Late Triassic before dinosaurs began to dominate the terrestrial communities.

[Ludwigia]

Nothosaurus sp. rib section from the Obere Muschelkalk Formation, Ladinian, Middle Triassic at Rothenburg ob der Tauber, Bavaria.

 

[Ludwigia]

Cadoceras sublaeve. Early Callovian calloviense zone, Middle Jurassic. Found at the Dairy Farm quarry near Ashton Keynes, Wiltshire, GB.

 

[siteseer]

 Here's a shark tooth from the Early Cretaceous, Upper Albian-age, Pawpaw Formation, Motorola site, Tarrant County, Texas.  The species is Squalicroax pawpawensis and it measures10mm along the mesial edge (the leading edge).

[siteseer]

Here are two teeth of Plesiadapis from the Late Paleocene of Cernay-les-Reims, France.  The longer tooth at 21mm is a complete incisor and the smaller tooth at just over 11mm is maybe a first premolar.  Plesiadapis was an early primate that lived before more advanced and more recognizable forms similar to lemurs and tarsier appeared.  In fact, Plesiadapis was rather variable in form species to species.  One would have looked very squirrel-like and another might have looked a little chunkier almost like a groundhog but these animals were actually present when only the earliest rodents were present.  It appears Plesiadapis was primarily a tree-dweller but perhaps not an acrobat equal to more modern primates.

 

I should add that the incisor is not like a rodent's.  It isn't as sharp-edged and is broader.  It might have been used more like a scoop when feeding on juicy fruit but it would have been as suitable for gnawing into fruits, flowers, and insects.

 

A friend received these teeth in a trade with a French collector back in the 1960's.  The main thing they were trading was Early Cenozoic shells but the French collector added these to the trade because he knew my friend had an interest in vertebrates.  My friend gave them to me about twenty years ago after he realized I had a variety of vertebrate fossils in my collection.  He gave a few other teeth from the locality and I will have to get those photographed as well for this thread.

[siteseer]

Here are two Metasequoia occidentalis sprays from the Middle Eocene Tranquille Shale, Cache Creek, British Columbia, Canada.  Metasequoia, a conifer genus, appeared during the early part of the Late Cretaceous (Cenomanian age).  It was hardy enough to survive the K/T extinction and thrived in North America during the Paleocene and Eocene.  It ranged as far north as Ellesmere Island, indicating a wet, mild climate even in northernmost Canada at the time.  However, climates began trending noticeably drier, and cooler by the Late Eocene.  Metasequoia's range shrank over time and died out in North America by the end of the Miocene.  It was even considered extinct worldwide until it was discovered alive in China in the 1940’s.  Since then, it has been successfully re-introduced into North America.

 

I received this specimen and numerous others from the late John Leahy who traveled under the name, Jbswake, here on the forum.  I had asked him for maybe 10 specimens for some fossil kits I was making for kids and teachers.  He sent a box full of what he considered extras but there were some very nice specimens like this.  He didn't want anything in trade and didn't even want to be compensated for the shipping.  He barely knew me and then I heard  he passed away less than two years later.  I will always remember his generosity.

 

 

[siteseer]

And now two whale teeth from the Late Oligocene Chandler Bridge Formation, Summerville, Dorchester County, South Carolina.  It tough or impossible to say which whales they belonged to.  The Oligocene was a time after the most ancient whales (archaeocetes) had died out but i was populated by many archaic groups living among the earliest members of some modern groups (sperm whales, baleen whales).  The teeth of many of these them are too similar to tell apart.  The tooth on the left (just over 20mm long) looks vaguely like a mini sperm whale tooth and the one on the right (24mm long) leans more squalodont in form.

 

Some of these toothed whales would have looked less like "Flipper" or Shamu and more like one of those funky river dolphins of the Amazon or the Ganges River.

[FranzBernhard]

Some tiny, abundant herbivore / detritivore (?) gastropods from the Styrian Basin in nice arrangement. However, its impossible to have the third one in focus without stacking.

Franz Bernhard

[Mochaccino]

Here's a pair of small indeterminate bivalves in matrix from the Pliocene Florida Everglades of USA. Not the famous Rucks Pit clams, but they're still filled with calcite crystals that fluoresce under UV

Edited July 4, 2022 by Mochaccino

[Missourian]

Mastodon tooth

Mammut sp.

Kansas River gravel, Pleistocene

Wyandotte County (or nearby), Kansas

 

 

[PR0GRAM]

Grypania Spyralis: Upper Doushantuo Formation at Wenghui, Jiangkou, Guizhou China - Ediacaran
A macroalga found in the fossil record from 2.1 bya to the end of the Ediacaran.

[piranha]

2 hours ago, PR0GRAM said:

Grypania Spyralis: Upper Doushantuo Formation at Wenghui, Jiangkou, Guizhou China - Ediacaran

A macroalga found in the fossil record from 2.1 bya to the end of the Ediacaran.

 

Wikipedia is a wonderful resource and constantly improving, but unfortunately is incorrect on this one. They cited the relevant papers but have inadvertently switched the data: the previous estimate was 2.1 billion years old. Improved dating methodology gives a more precise age: 1874 ± 9 Ma.

 

Schneider, D.A., Bickford, M.E., Cannon, W.F., Schulz, K.J., Hamilton, M.A. 2002

Age of Volcanic Rocks and Syndepositional Iron Formations, Marquette Range Supergroup:

Implications for the Tectonic Setting of Paleoproterozoic Iron Formations of the Lake Superior Region.

Canadian Journal of Earth Sciences, 39(6):999-1012  PDF LINK

 

Han, T.M., Runnegar, B. 1992

Megascopic Eukaryotic Algae from the 2.1-Billion-Year-Old Negaunee Iron-Formation, Michigan.

Science, 257:232-235

[PR0GRAM]

10 minutes ago, piranha said:

 

Wikipedia is a wonderful resource and constantly improving, but unfortunately is incorrect on this one. They cited the relevant papers but have inadvertently switched the data: the previous estimate was 2.1 billion years old. Improved dating methodology gives a more precise age: 1874 ± 9 Ma.

 

Schneider, D.A., Bickford, M.E., Cannon, W.F., Schulz, K.J., Hamilton, M.A. 2002

Age of Volcanic Rocks and Syndepositional Iron Formations, Marquette Range Supergroup:

Implications for the Tectonic Setting of Paleoproterozoic Iron Formations of the Lake Superior Region.

Canadian Journal of Earth Sciences, 39(6):999-1012  PDF LINK

 

Han, T.M., Runnegar, B. 1992

Megascopic Eukaryotic Algae from the 2.1-Billion-Year-Old Negaunee Iron-Formation, Michigan.

Science, 257:232-235

Thank you for correcting me! I even have a paper on Macroalgal Holdfast from Doushantuo and didn’t bother to check their citations… where the updated dates are included

[siteseer]

For the Cambrian, here's a plate with several Elrathia kingi and an agnostid trilobite.  It was a gift from a friend.  The plate is 3 7/8 x 8 3/4 inches (roughly 9.8cm x 22.2cm).

 

Middle Cambrian

Wheeler Shale

Millard County, Utah

 

 

[Missourian]

 

Favosites sp.
Ordovician
Truman Reservoir, Missouri

 

 

 

This is one of my first fossil finds as a kid. I was bored while fishing with my dad, so I walked the rocky slope below the high-water mark. At the time I thought it was a 'petrified wasp nest'.

 

[JamieLynn]

I only have a few fossils that are from a Silurian layer - this one isn't great, but i like it.

Brachiopod

 

[Mochaccino]

A Devonian Cupressocrinites sp. crinoid plate from the Draa Valley of Morocco, Africa. Crown measures about 12 cm. Quite nice I think relative to how ground up and poorly prepped these can typically be.

 

 

 

Edited July 6, 2022 by Mochaccino

[Mark Kmiecik]

Upper Carboniferous period. Pennsylvanian. Moscovian/Kasimovian boundary. Francis Creek Shale member directly above the Colchester Coal of NE Illinois.

 

 

Edited July 6, 2022 by Mark Kmiecik
fix typo - add info

[siteseer]

Eryops megacephalus - tooth

Early Permian

Ryan Formation

Waurika, Jefferson County, Oklahoma

 

Eryops was one of the largest amphibians (5-10 feet long) of the Permian Period - maybe formidable enough to hold its own against predators like Dimetrodon.  Its well-ossified skeleton and large limbs indicate that it had a more terrestrial lifestyle than other amphibians of its time so it was rather advanced in that way.  This tooth measures 18mm.

 

 

[siteseer]

Ammonite - roughly 17mm in diameter

Middle Triassic

Star Peak Formation

Lovelock, Nevada

 

I used to see a pretty good selection of Triassic ammonites from Nevada at shows in California and Arizona, but in the years before COVID, I saw hardly any.  Some of the sites are remote and it seems most collectors these days are looking for more convenient places to go.  With gas costing around 2 bucks more a gallon than at the beginning of the year, you can't blame anybody for that. 

[Paleorunner]

Aeger elegans. Jurassic inf. Tithonian. Solnhofen

 

[Paleorunner]

Plesiosaur tooth. Zarafasaura oceanis.
Cretaceous, Maastrichtian. Ouled Abdoun.. Morocco.

 

[Ludwigia]

Palaeocarcharodon orientalis from the Paleocene at Khouribga, Morocco.