Fossillarry's Mammals

[siteseer]

As Larry familiarizes himself with how to attach photos to his posts, I will be posting for him.  Larry is a humble collector of mammals but he is very experienced.  He is one of the rare mammal collectors with knowledge of Eocene-Pleistocene groups.  Most collectors specialize in Oligocene or Miocene-Pleistocene of North America but he knows a wide variety of forms specializing in ungulates (hoofed mammals of the Perissodactyla and Artiodactyla.  He's hunted from California to Nebraska and South Dakota to Texas.

 

The first specimen he'd like to share with the forum is a 2-tooth maxilla section of Cardiolophus, an early tapiroid from the Early Eocene, Willwood Formation of Bighorn Basin, Wyoming.  A tapiroid is a perissodactyl (odd-toed ungulate) that currently appears to be part of the lineage that connects to modern tapirs or is likely related to that lineage.  Larry might ask me to clarify that further.  One thing to remember about Cardiolophus is that it was part of a great radiation of mammals that appeared at the base of the Eocene.  It was the time of the earliest horse, tapir, chalicothere, and titanothere..  These animals were very much alike in form and dentition as they descended from a common ancestor in the Late Paleocene.

 

Also attached is a photo of jaw sections of Cardiolophus.

 

Jess

   

[Ludwigia]

Thanks for posting this for Fossillarry, Jess. I'm already looking forward to the next chapters.

[Shellseeker]

4 hours ago, siteseer said:

He is one of the rare mammal collectors with knowledge of Eocene-Pleistocene groups. 

I am envious and impressed.  I also looked foward to future posts.  Thanks, Jess

[siteseer]

Here are two Homogolax specimens: a 4-tooth jaw section (last premolar and the three molars) and a lower third molar in a piece of jaw.  Like Cardiolophus, Homogolax is another tapiroid.  After doing more reading and talking to Larry, tapiroids are not necessarily related to tapirs.  They are basal perissodactyls (forms close to the ancestor of perissodactyls) with skeletal characters similar to tapirs but their relationships remain to be clarified.  Larry added that another Early Eocene tapiroid, Heptodon, may actually be an early tapir or related to the group.

 

I just noticed that Larry didn't add anything for scale.  I can say a Homogolax lower third molar is about 5/8 inches long (maybe 1.6cm) as measured along the jaw..

 

Jess

[Kiros]

This is the kind of post that was missing in the forum! As a mammal lover I can't wait for you to post more great findings!! 

[siteseer]

Larry has sent me more photos.  Here's a maxilla of a juvenile with Dp2-M2 (that means upper deciduous 2nd upper to the 2nd upper molar) of Homogalax protapirinus, a tapiroid.  The specimen is from the Wasatchian (North American Land Mammal Age that accounts for about the first 4-5 million years of the Eocene Epoch - roughly 50-55 million years ago), Willwood Formation, Bighorn Basin, Wyoming.

 

The Wasatchian (early Eocene) was the warmest time in the Cenozoic.  Tropical forest covered a large part of western North America from New Mexico through Wyoming, Colorado, Utah, Wyoming, and all the way to northern Canada.  All those great fish, insect, and plant fossils of the Green River Formation were deposited at the very end of or just after the Wasatchian.  World climates started to cool as a general trend after the Wasatchian.  Tropical animals and plants became less diverse and some genera became extinct or survived in other parts of the world.  The Wasatchian was a time before there were cats, dogs, bears, camels and only the earliest elephant and whale ancestors were present.  In fact whales still had feet at that time.  The oldest known bats and rodents lived at that time.  Overall, mammals were small.  The largest one was the size of a dairy cow.

 

Jess

[siteseer]

Here's a maxilla piece of a juvenile Homogalax protapirinus with Dp4-M2 (deciduous upper 4th premolar to the 2nd upper molar - also from the early Eocene of the Powell area, Bighorn Basin, Wyoming.

[siteseer]

Here are some Homogalax upper teeth:  maxilla piece on the left has P3-4; middle piece has M2-3, and the tooth on the right is an isolated M3.  These are also from the Powell area, Wyoming.

[siteseer]

Here are two Homogolax protapirinus lower jaw specimens:  the one on the left contains p3-4, m1 and most of m2;  jaw on the right has p4-m3.  Both are from near Powell Wyoming (early Eocene, Wasatchian age).

[siteseer]

Larry says this tooth is either an m1 or m2 from the tapiroid, Heptodon sp. I believe.  It's larger then that of Homogalax with a slightly taller crown and the cross lophs are stronger.  The hypoconulid is smaller then in Homogalax and the front half (trigonid) of the tooth is wider than in Homogalax.

 

Heptodon, also an early Eocene form, is considered closer to the tapir lineage than Homogolax but the earliest true tapir has been deemed to be Protapirus, a Uintan age (late-middle Eocene) genus.

 

 

 

[Shellseeker]

On 9/29/2020 at 1:59 AM, siteseer said:

The Wasatchian (early Eocene) was the warmest time in the Cenozoic.  Tropical forest covered a large part of western North America from New Mexico through Wyoming, Colorado, Utah, Wyoming, and all the way to northern Canada.  All those great fish, insect, and plant fossils of the Green River Formation were deposited at the very end of or just after the Wasatchian.  World climates started to cool as a general trend after the Wasatchian.  Tropical animals and plants became less diverse and some genera became extinct or survived in other parts of the world.  The Wasatchian was a time before there were cats, dogs, bears, camels and only the earliest elephant and whale ancestors were present.  In fact whales still had feet at that time.  The oldest known bats and rodents lived at that time.  Overall, mammals were small.  The largest one was the size of a dairy cow.

 

Jess

 

I appreciate the immense expertise that you bring to the table,  Jess. Your dialogue adds volumes to the already significant value of the photos.

[jpc]

These are great (The pix are a bit fuzzy), but these will help me ID my Eocene mammals.  Does Larry know non-perissodactyls from the Eocene?  

 

[siteseer]

11 hours ago, jpc said:

These are great (The pix are a bit fuzzy), but these will help me ID my Eocene mammals.  Does Larry know non-perissodactyls from the Eocene?  

 

 

Hi JP,

 

Larry has sent me a number of photos and I am posting the best of them.  He is getting an idea of how clear they need to be.

 

Yes, he knows the "condylarths" (Hyopsodus, Phenacodus) and other oddball groups - genera like Ectocion, Esthonyx.  He knows a primate when he sees one but identifying one to genus is not his specialty.  He has been able to do that, though.  As you know, the early Eocene of North America has a mix of some local Paleocene survivors along with some Asian and European immigrants and many of them died out by the late Eocene, which is the time you start to see forms familiar from the Oligocene.

 

Jess

[jpc]

11 hours ago, siteseer said:

 

Hi JP,

 

Larry has sent me a number of photos and I am posting the best of them.  He is getting an idea of how clear they need to be.

 

Yes, he knows the "condylarths" (Hyopsodus, Phenacodus) and other oddball groups - genera like Ectocion, Esthonyx.  He knows a primate when he sees one but identifying one to genus is not his specialty.  He has been able to do that, though.  As you know, the early Eocene of North America has a mix of some local Paleocene survivors along with some Asian and European immigrants and many of them died out by the late Eocene, which is the time you start to see forms familiar from the Oligocene.

 

Jess

cool.  I can ID a lot of these to the order, but then it gets challenging.  Upper molars are easier than lowers.  And the literature for IDing is so wide and spread out.  I did a trip to the U of Wyoming before covid to compare some of our museum specimens with theirs and was able to figure out a few.  But there is still a lot of learning to do.  One of my retirement goals is to actually learn them  well.  (And prep out my garageful of fossils), but that is 10 years away.  

 

Thanks again for posting these.  

[siteseer]

3 hours ago, jpc said:

cool.  I can ID a lot of these to the order, but then it gets challenging.  Upper molars are easier than lowers.  And the literature for IDing is so wide and spread out.  I did a trip to the U of Wyoming before covid to compare some of our museum specimens with theirs and was able to figure out a few.  But there is still a lot of learning to do.  One of my retirement goals is to actually learn them  well.  (And prep out my garageful of fossils), but that is 10 years away.  

 

Thanks again for posting these.  

 

Yes, Early Eocene teeth make up a whole other world of experience for a mammal collector.  Larry told me that Matthew wrote a helpful reference and I need to get the title and look for that.  I thought I had an upper molar nailed down as at least marsupial but Larry advised me to look at some of the early carnivores because their upper molars can be that triangle shape too.  I have some unidentified teeth that don't fit what I've seen before so I might have something like an early uintathere relative or something else with no modern relatives.

 

In the late 80's I met Father Floyd Jenkins, a Jesuit priest who taught biology at Loyola Marymount.  His hobby was fossil collecting and he had all kinds of connections among researchers.  He also had very particular interests.  He was a mollusk expert and traded with collectors all over the world.  He also studied Cretaceous and Eocene mammals.  He identified all the specimens that Allen Graffham had in the 80's.  One of his side projects was to assemble a collection of calcanea from as many different mammal groups (shooting for genera but he would take something ID'ed to family) as possible.  He also screened matrix from the Sharps Formation in search of "insectivores" (now considered to belong to the Order Eulipotyphia) for another researcher.  I hope all his specimens found a home because I'm not sure the university was interested in keeping it all.

 

I was able to hang out with Father Jenkins in his office/lab/storeroom from time to time in the 90's.  I learned a lot from him about mammals.  He was an incredibly knowledgeable guy.  He seemed to know something substantial about many subjects and yet he was so humble.  I want to be like him when i grow up.

 

Anyway, Larry is taking more photos.  He wants to do a lot of horse teeth.

 

Jess

[jpc]

32 minutes ago, siteseer said:

 

Yes, Early Eocene teeth make up a whole other world of experience for a mammal collector.  Larry told me that Matthew wrote a helpful reference and I need to get the title and look for that.  I thought I had an upper molar nailed down as at least marsupial but Larry advised me to look at some of the early carnivores because their upper molars can be that triangle shape too.  I have some unidentified teeth that don't fit what I've seen before so I might have something like an early uintathere relative or something else with no modern relatives.

 

In the late 80's I met Father Floyd Jenkins, a Jesuit priest who taught biology at Loyola Marymount.  His hobby was fossil collecting and he had all kinds of connections among researchers.  He also had very particular interests.  He was a mollusk expert and traded with collectors all over the world.  He also studied Cretaceous and Eocene mammals.  He identified all the specimens that Allen Graffham had in the 80's.  One of his side projects was to assemble a collection of calcanea from as many different mammal groups (shooting for genera but he would take something ID'ed to family) as possible.  He also screened matrix from the Sharps Formation in search of "insectivores" (now considered to belong to the Order Eulipotyphia) for another researcher.  I hope all his specimens found a home because I'm not sure the university was interested in keeping it all.

 

I was able to hang out with Father Jenkins in his office/lab/storeroom from time to time in the 90's.  I learned a lot from him about mammals.  He was an incredibly knowledgeable guy.  He seemed to know something substantial about many subjects and yet he was so humble.  I want to be like him when i grow up.

 

Anyway, Larry is taking more photos.  He wants to do a lot of horse teeth.

 

Jess

As I understand it, marsupial upper teeth have little cusplets along the labial edge.  (Stylar cusps A through D in this drawing, which is looking onto the chewing surface)  This is pretty distinctively marsupial in the late Cretaceous ones.  And they are small, much smaller than any uintathere. 

 

Note: I am pretty familiar with tooth nomenclature, so it is tough for me to see if this drawing makes sense to the uninitiated, or not. 

 

[siteseer]

Right.  The possible marsupial tooth is quite small.  I wasn't confusing that with a tooth of a uintathere relative.  I have unidentified teeth of different sizes and morphologies.  At some point I should get them photographed and post the shots on the Forum.

 

I think those two figures are very enlightening.  They provide the technical terms for the little bumps, basins, and ridges of a mammal upper and lower tooth.  Not every tooth is going to exhibit all those features but knowing those features have names is the beginning of understanding any mammal tooth whether it's a modern horse or mammal that lived only during the Early Eocene.

 

Jess

[fossillarry]

My largest Hyracotherium tooth . It's an M1 or M2 and about 11mm long. From the Willwood formation, Bighorn Baden, Wyo. This my first attempt at posting photos on the Forum without Jess's help. As my skills improve I'll be adding some non Peridsodsctyl teeth as well other mammals from the Lower,Middle and Upper Eocene to this thread.

[Ludwigia]

8 hours ago, fossillarry said:

My largest Hyracotherium tooth . It's an M1 or M2 and about 11mm long. From the Willwood formation, Bighorn Baden, Wyo. This my first attempt at posting photos on the Forum without Jess's help. As my skills improve I'll be adding some non Peridsodsctyl teeth as well other mammals from the Lower,Middle and Upper Eocene to this thread.

 

Thanks for making the extra effort. Looking forward to your future posts.

[fossillarry]

Corypdon upper M3. Corypdon is one of the first archaic ungulates to achieve large body size. This specimen is from the Willwood Formation,Wasatchian Early Eocene,Bighorn Basin Wyoming.

 

[fossillarry]

This is an upper M1/2 of Esthonyx. Esthonyx is a member of the mammalian order Tillodontia.  Esthonyx  is known from the late Paleocene to the  early Bridgerian in North America. Tillodonts are known from China(Early Paleocene to Late Eocene) and North America(Late Paleocene to Late Middle Eocene).  Esthonyx and Tillodonts in general have clawed feet and rodent-like incisors indicating a rooting and digging way of life.   

[fossillarry]

This is a lower jaw fragment of Esthonyx with half of M1 and M2/3 of the right side. It as well as the upper tooth in the above  photo are from the Willwood Formation,Early Eocene of Wyoming.

[jpc]

Is that Hyracotherium dentition painted on the background?

[fossillarry]

No it's a cast of Hyracotherium my friend made for me that I use to prop up specimens  that I am photographing.

[jpc]

2 hours ago, fossillarry said:

No it's a cast of Hyracotherium my friend made for me that I use to prop up specimens  that I am photographing.

well, I got the Hyracotherium part right.  That's all the matters.