Mammals (rodents, insectivores, marsupials and carnivores) from the Eocene/Oligocene M&M Ranch in Nebraska

[siteseer]

Wow, that's great Marco Sr.  I have a couple of friends who are going to want to read that paper.

[MarcoSr]

On 2/14/2022 at 12:04 AM, siteseer said:

Wow, that's great Marco Sr.  I have a couple of friends who are going to want to read that paper.

 

The manuscript will be a stand-alone publication in the Journal Paludicola, which is a peer-reviewed journal published under the auspices of the Rochester Institute of Vertebrate Paleontology (RIVP).  Dr. William W. Korth, one of the manuscript's authors, is also one of the two editors for the Journal Paludicola.

 

Marco Sr.

Edited April 23, 2022 by MarcoSr
removed free download

[digit]

Spectacular! Looking forward to seeing that publication.

 

 

Cheers.

 

-Ken

[fossilhunter21]

That is awesome! I am really looking forward to seeing that publication!

 

-@fossilhunter21

[Sjfriend]

Wow! That is quite an addition to the known fauna of the area! Great work sir!

[ClearLake]

I just read through this whole thread, what an interesting project!  It certainly will be interesting and gratifying for those involved to see the published results.  Well done Marco Sr (with help from the kids).  

[MarcoSr]

Great news, the paper is published.

 

PALUDICOLA SCIENTIFIC CONTRIBUTIONS of the ROCHESTER INSTITUTE OF VERTEBRATE PALEONTOLOGY Special Issue VOLUME 13 NUMBER 4 1 MAY 2022

"Fossil mammals from ant mounds situated on exposures of the Big Cottonwood Creek Member of the Chadron Formation (latest Eocene-early Oligocene), Sioux County, Nebraska  - William W. Korth, Clint A. Boyd, Jeff J. Person, and Deborah K. Anderson"

 

https://rivp-paludicola.org/home-page/

 

 

 

 

Below is the abstract:

 

ABSTRACT

For over a century the mounds of harvester ants (Pogonomyrmex spp.) have been targeted by paleontological field crews as sources of concentrated microvertebrate fossils that facilitate the collection of large numbers of specimens with a small investment of time. This study describes a collection of over 6,000 identifiable micromammal teeth and jaws recovered from 19 ant mounds in Sioux County, Nebraska south of Toadstool Geologic Park. All of these ant mounds are situated on rocks of the Big Cottonwood Creek Member and their stratigraphic positions span from seven meters below to five meters above the upper purplish-white layer (UPW). The large sample size and stratigraphic position of this collection allows for the documentation of the micromammal faunae of this region, investigation of patterns of faunal change across the Chadronian-Orellan boundary, and identification of the local stratigraphic position of the Chadronian-Orellan boundary.

Over 80 mammalian taxa are recognized in this collection, including ten new species and four new genera. Among the rodents nine new species, including three new genera, are described. The new genera include the cylindrodont Siouxlindrodon (S. sullivani n. sp.) and the aplodontids Costepeiromys (C. attasorus n. sp.) and Protansomys (P. gulottai n. sp.). The additional new rodent species consist of the ischyromyid Ischyromys brevidens n. sp., the eomyids Paradjidaumo patriciae n. sp., Yoderimys massarae n. sp., and Litoyoderimys grossus n. sp., the florentiamyid Kirkomys miriamae n. sp., and the sciurid Cedromus modicus n. sp. Among the Lipotyphla, the soricid Domnina compressa Galbreath, 1953, is referred to a new genus Noritrimylus (as N. compressus), along with N. dakotensis (Repenning, 1967) and N. metaxy (Korth, 2020a), and a new species of oligoryctid, Oligoryctes tenutalonidus n. sp., is recognized.

The large sample size available in this study also improved the understanding of the morphology and distribution of several previously described taxa. Tooth positions that were previously unknown for several taxa were identified and described for the first time (e.g., Adjidaumo intermedius; Eutypomys hibernodus, Ecclesimus tenuiceps, Micropternodus montrosensis). In some cases, the number of specimens here referred to specific taxa exceeds the total number of specimens previously known for that taxon (e.g., A. intermedius). A single chiropteran specimen (partial dentary with m3) and three isolated omomyid primate teeth are present in the collection but cannot be confidently referred to any known species. A partial M2 is referred to the borophagine canid Otarocyon macdonaldi, potentially representing the earliest occurrence of borophagines in North America.

The majority of the non-lagomorph specimens identified in this study (~69 percent) are referred to taxa that elsewhere first appear in Orellan or younger faunae and Orellan taxa dominate the faunal lists of all 19 ant mounds regardless of their stratigraphic position. This prevalence of Orellan taxa results from downslope transport of Orellan specimens into the foraging range of the ant mounds, an important factor that must be considered when working with ant mound collections. To compensate for that effect the local last appearance datums of 14 Chadronian taxa (including three new species) were used to estimate the local stratigraphic position of the Chadronian-Orellan boundary instead of the local first appearance datums of Orellan taxa. It is estimated that the boundary is situated at the distinctive layer derived from volcanic ash (=UPW; ±2 meters), in close agreement with previous studies.

 

 

Marco Sr.

[digit]

 

Cheers.

 

-Ken

[fossilhunter21]

Yay!!!  That is wonderful news!  

Thank you for sharing it with us! 

 

-Micah

Edited May 17, 2022 by fossilhunter21

[JohnJ]

Congratulations, Marco!

 

 

[MarcoSr]

23 hours ago, digit said:

 

Cheers.

 

-Ken

 

22 hours ago, fossilhunter21 said:

Yay!!!  That is wonderful news!  

Thank you for sharing it with us! 

 

-Micah

 

7 hours ago, JohnJ said:

Congratulations, Marco!

 

 

 

I'm now hearing that the squamate researcher (snakes, lizards and legless lizards) will start looking in detail at the squamate specimens from the M&M Ranch this summer.  Covid and other projects like his work at the Messel Pit and with climate papers have prevented him from doing so to date.  He is especially interested in the ranch specimens because they are from sediments just before, at, and just after the Eocene/Oligocene boundary contact in Nebraska and will help support his climate theories.

 

Marco Sr.

[Brandy Cole]

Awesome! Congratulations!

[digit]

Very cool! Looking forward to the continuation of this story.

[fossilhunter21]

Even more wonderful news! I am looking forward to the next update!

 

-Micah

Edited May 18, 2022 by fossilhunter21

[Coco]

Hi,

 

Very good news ! Congrats Marco !

 

Coco

[MarcoSr]

On 5/17/2022 at 9:48 PM, Brandy Cole said:

Awesome! Congratulations!

 

On 5/17/2022 at 10:38 PM, fossilhunter21 said:

Even more wonderful news! I am looking forward to the next update!

 

-Micah

 

On 5/18/2022 at 2:41 AM, Coco said:

Hi,

 

Very good news ! Congrats Marco !

 

Coco

 

Thank you.  The paper will hopefully help with the identification of some of the Nebraska micro mammal specimens.

 

Marco Sr.

[MarcoSr]

On 5/17/2022 at 9:56 PM, digit said:

Very cool! Looking forward to the continuation of this story.

 

Thank you, I am too.

 

Marco Sr.

[mr.cheese]

I enjoyed that, a very good read! I look forward to the next update also.

[MarcoSr]

Below is a picture of two displays (each 34.5x 12.5 inches), depicting the 10 new mammal species (figures from the Paludicola paper) from my sons' M&M Ranch, that my wife and I just put together that are now hanging on my wall.  I'm waiting on two brass nameplates that have engraved "New Mammal Species M&M Ranch Nebraska" which I'll add to the bottom of each display.

 

 

 

 

Marco Sr.

[Al Dente]

Nice displays.

[fossilhunter21]

Those are some awesome displays! 

 

-Micah

[MarcoSr]

Here are my final displays with the nameplates added.

 

 

              

 

 

Marco Sr.

[Coco]

Hi,

 

Nice result !

 

Coco

[fossilhunter21]

Those are really nice looking! I think you did an awesome job on those. 

 

-Micah

[jpc]

Ecxellent dispalys, marco