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

[Pleuromya]

These are mammal teeth that I purchased a few years ago. 

From the Upper Cretaceous Hell Creek Formation, Carter County, Montana. 

The largest measures 10mm and the small ones about 2mm each. 

[siteseer]

On 6/2/2023 at 10:11 AM, JamieLynn said:

Can I sneak in a Lower Cretaceous? 

Pseudodiadema aguilerai   Texas Glen Rose Formation

 

 

 

The whole point of this thread is that each post is younger than the last until we start over.  You should save an Early Cretaceous fossil for when we need it.  I can understand posting something out of order by mistake but why do it on purpose?  I've waited weeks to post something because I wasn't here whenever the Devonian came up. 

[siteseer]

This tooth appears to be just another incomplete Notidanodon tooth from the Paleocene of Morocco.  However, this one exhibits a wear facet on the main cusp which is unusual because that means the tooth might have stayed in the jaw longer than usual (or perhaps it just happened to get worn at that spot before final burial).  A broken cusp on one of these teeth is almost always rather ragged at the break.

 

Notidanodon sp.

extinct cow shark (hexanchid)

Paleocene

Oued Zem, Ouled Abdoun Basin, Morocco

40m wide

 

 

[siteseer]

Here's a jaw section of Hyracotherium, the earliest horse.  It's possible that it belongs to another genus that has been proposed recently.  In any case it's interesting not just because it's a specimen of the earliest horse but also because it shows the third molar starting to erupt so the animal was a young adult when it died.

 

Hyracotherium sp. ("Eohippus" in the old books) - jaw section

Early Eocene 

San Jose Formation

site in Rio Arriba County, New Mexico

22m long

Edited June 4, 2023 by siteseer

[siteseer]

On 6/2/2023 at 3:29 AM, Notidanodon said:

That’s in great condition!

 

Yes, it was a very generous gesture from an old friend I traded with.

[FranzBernhard]

Nine days and still no Oligocene has appeared... .

Franz Bernhard

[Pleuromya]

I don't have much left from the Oligocene, but this is a Palaeolagus hayendi mandible from the Brule Formation, Sioux county, Nebraska. It measures 17mm across. 

[Ludwigia]

Schizaster eurynotus from the Miocene Burdigalian from Sesimbra, Lisbon, Portugal.

 

 

 

[Pleuromya]

This echinoid is Temnechinus woodi from the Pliocene (Gelasian), Coralline Crag formation, Suffolk. 

 

Edited June 13, 2023 by Pleuromya
Added an extra photo

[Mochaccino]

The vast majority of my fossils are Paleozoic and I only have a handful of Pleistocene-aged fossils, but here is one of them and surely one of my favorites. An aquatic scavenger beetle of the genus Hydrophilus (still extant today), preserved with bitumen on a block of tar as is typical for tar pit fossils. This one is from the Wilshire-Hauser Pit, which was exposed during construction and was briefly publicly collectible during the 1970s. This is not technically the La Brea Tar Pits, but a different exposure just a few blocks away. Despite likely being from the same formation, to me the matrix and preservation seems distinct from the La Brea Pits and from any other similar locality in California such as the McKittrick and Maricopa pits.

 

Sabertooth tigers and dire wolves are cool and all, but I've always loved the invertebrates and insects from these Tar Pits because they are preserved in an incredibly unique manner that isn't seen anywhere else. 

 

Hydrophilus sp.
Wilshire-Hauser Pit

Rancho La Brea Formation

Los Angeles County, California, USA

 

 

Edited June 14, 2023 by Mochaccino

[Wrangellian]

20 hours ago, Pleuromya said:

This echinoid is Temnechinus woodi from the Pliocene (Gelasian), Coralline Crag formation, Suffolk. 

 

The ICS has added the Gelasian to the Pleistocene, so I guess we've technically got two consecutive Pleistocene fossils here.

[PR0GRAM]

I'll try to cover the Ediacaran a few more times if I can.

 

Another kinda uncommon bit of material.

This comes from the Dengying Formation of south China.

Uppermost Ediacaran.

It is most similar to Tawuia like aglae.

[Pleuromya]

On 6/14/2023 at 11:20 AM, Wrangellian said:

The ICS has added the Gelasian to the Pleistocene, so I guess we've technically got two consecutive Pleistocene fossils here.

Thank you, I didn't know that so I will have to update my label for it. 

[siteseer]

On 6/14/2023 at 2:10 AM, Mochaccino said:

The vast majority of my fossils are Paleozoic and I only have a handful of Pleistocene-aged fossils, but here is one of them and surely one of my favorites. An aquatic scavenger beetle of the genus Hydrophilus (still extant today), preserved with bitumen on a block of tar as is typical for tar pit fossils. This one is from the Wilshire-Hauser Pit, which was exposed during construction and was briefly publicly collectible during the 1970s. This is not technically the La Brea Tar Pits, but a different exposure just a few blocks away. Despite likely being from the same formation, to me the matrix and preservation seems distinct from the La Brea Pits and from any other similar locality in California such as the McKittrick and Maricopa pits.

 

Sabertooth tigers and dire wolves are cool and all, but I've always loved the invertebrates and insects from these Tar Pits because they are preserved in an incredibly unique manner that isn't seen anywhere else. 

 

Hydrophilus sp.
Wilshire-Hauser Pit

Rancho La Brea Formation

Los Angeles County, California, USA

 

 

 

How is the matrix different?  I've processed a lot of tar, washing it in acetone or kerosene or carefully sifting through loose matrix.  You can get a range of matrix from that loose brown matrix which may be the younger stuff (rich in bird and rodent material with some coyote) but some of it may be older as I found parts of a dire wolf maxilla in it once, to very hard, shiny black chunks.  You'd think it was at least a few million years old but it's maybe 40,000 at most.  I don't really know.

 

[Mochaccino]

45 minutes ago, siteseer said:

 

How is the matrix different?  I've processed a lot of tar, washing it in acetone or kerosene or carefully sifting through loose matrix.  You can get a range of matrix from that loose brown matrix which may be the younger stuff (rich in bird and rodent material with some coyote) but some of it may be older as I found parts of a dire wolf maxilla in it once, to very hard, shiny black chunks.  You'd think it was at least a few million years old but it's maybe 40,000 at most.  I don't really know.

 

 

This is a purely personal, subjective observation of mine, but the typical La Brea Tar Pit matrix from LA county seems dark brown, medium to fine-grained, almost soil or mud-like. I actually do have two pieces from this locality. The Wilshire-Hauser material, as you can see in the piece I posted here, seems to have more shiny/oily and chunky, jet-black matrix. McKittrick Tar Pit material from Kern County seems the most coarse-grained, with big debris and pebbles etc. throughout, and also more brown-colored. I don't know if that's a consistent distinction but it's a trend I've noticed. Obviously I haven't worked directly with any of the material.

 

[FranzBernhard]

Is this topic coming to an end? Nearly two weeks since the last entry and I don´t have any Cambrian .

Franz Bernhard

[siteseer]

39 minutes ago, FranzBernhard said:

Is this topic coming to an end? Nearly two weeks since the last entry and I don´t have any Cambrian .

Franz Bernhard

 

I don't think it's coming to an end but maybe it needs a break until it's discovered by a member who missed the flurries of posts of the past year and who has a lot of early Paleozoic fossils to show.  Maybe that gets the attention of a new group of posters.  Over the past 13-14 years, I've seen old threads pop back up especially the "Show us your..." kinds.

 

The next time I'm at a big fossil show at Denver or Tucson, I'll probably look for interesting specimens from the Silurian, Permian, and Triassic - times that have been speed bumps in our race through (not against) time.

[Wrangellian]

4 hours ago, FranzBernhard said:

Is this topic coming to an end? Nearly two weeks since the last entry and I don´t have any Cambrian .

Franz Bernhard

I've got more Cambrian but it's a pain to take photos, process them and upload them!

Does no one out there have even an Elrathia kingii to fill the gap?

[Missourian]

18 hours ago, FranzBernhard said:

Is this topic coming to an end? Nearly two weeks since the last entry and I don´t have any Cambrian .

Franz Bernhard

 

Just wait until the Carboniferous for the speed to pick up

 

--------------

 

5 mm trilobite

Brachyaspidon microps

Wheeler Shale, Cambrian

House Range, Utah, USA

 

[Ludwigia]

9 hours ago, Missourian said:

Just wait until the Carboniferous for the speed to pick up

 

 

Sigillaria tessellata from Saarland, Germany. Late Carboniferous.

[FranzBernhard]

Very nice, @Ludwigia, but just lets go on with the Ordovician now .

Franz Bernhard

[Pleuromya]

These are the Eocrinoid Ascocystites sp. from the Lower Ordovician of El Kaid Errami, Morocco. The whole plate measures 21.8 cm across. 

Edited July 2, 2023 by Pleuromya

[Ludwigia]

6 hours ago, FranzBernhard said:

Very nice, @Ludwigia, but just lets go on with the Ordovician now .

Franz Bernhard

Oops! I wasn't thinking. And we still need some things from the Silurian and Devonian to fill in my unintentional gap

[Isotelus2883]

Lower Silurian-

Rielaspis cf. elegantula moult

Thornloe or Earlton Fm

Temiskaming, Ontario

[Ludwigia]

Ok. I'll fill in the Devonian now. Calceola sp. from the Eifelian Hanonet Formation at Resteigne, Belgium.