Ungulates of the middle Miocene Monarch Mill Formation, Churchill County, Nevada, USA
A middle Miocene, early Barstovian land mammal age vertebrate assemblage, the Eastgate local fauna (LF), is known in the basal-most part of the Monarch Mill Formation. This rich assemblage of fossil vertebrates occurs within the Middlegate Basin in Churchill County, Nevada, USA. The Eastgate LF...
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| Language: | English |
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Institute of Paleobiology PAS
2022-03-01
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| Series: | Acta Palaeontologica Polonica |
| Subjects: | |
| Online Access: | https://www.app.pan.pl/archive/published/app67/app009072021.pdf |
| _version_ | 1818256316706062336 |
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| author | KENT S. SMITH NICHOLAS J. CZAPLEWSKI MARGERY C. COOMBS |
| author_facet | KENT S. SMITH NICHOLAS J. CZAPLEWSKI MARGERY C. COOMBS |
| author_sort | KENT S. SMITH |
| collection | DOAJ |
| description | A middle Miocene, early Barstovian land mammal age vertebrate assemblage, the Eastgate local fauna (LF), is known
in the basal-most part of the Monarch Mill Formation. This rich assemblage of fossil vertebrates occurs within the
Middlegate Basin in Churchill County, Nevada, USA. The Eastgate LF includes the fossil remains of fish, amphibians,
reptiles, birds, and over 25 families of mammals. Previous studies on the mammalian remains have revealed several
endemic taxa of rodents and carnivores. Herein, we describe the ungulates, which include two taxa from two families of
Artiodactyla (Ticholeptus sp., Merycoidodontidae and Barbouromeryx trigonocorneus, Palaeomerycidae) and three taxa
from three families of Perissodactyla (Equidae gen. et sp. indet., Moropus merriami, Chalicotheriidae, and Teleoceras
sp., Rhinocerotidae). Independent paleobotanical evidence nearly contemporaneous with the vertebrates indicates forest
and shrubland paleovegetation, and suggests that the area had been uplifted to 2700–2800 m paleoaltitude. Therefore,
this local fauna adds a rare glimpse of a medium-to high-altitude vertebrate community in the intermountain western interior of North America. Temporally-restricted taxa (especially the rodent Tardontia nevadans and chalicothere
Moropus merriami) reinforce the early Barstovian age of the Eastgate LF and are consistent with tephrochronological
dates and radiometric analyses. The presence of Barbouromeryx trigonocorneus at Eastgate is significant in that its
occurrence potentially represents a temporal range extension into the early Barstovian (previously known from latest
Arikareean to middle Hemingfordian), and extends the paleobiogeographic range from the Great Plains to the Great
Basin. Unequivocally, the ungulates and other mammals of the Eastgate LF support the presence of a temperate forest
ecosystem in the Great Basin just subsequent to the Miocene Climatic Optimum. |
| first_indexed | 2024-12-12T17:25:49Z |
| format | Article |
| id | doaj.art-45eae095918741ac88bdb41f7cb1a221 |
| institution | Directory Open Access Journal |
| issn | 0567-7920 1732-2421 |
| language | English |
| last_indexed | 2024-12-12T17:25:49Z |
| publishDate | 2022-03-01 |
| publisher | Institute of Paleobiology PAS |
| record_format | Article |
| series | Acta Palaeontologica Polonica |
| spelling | doaj.art-45eae095918741ac88bdb41f7cb1a2212022-12-22T00:17:31ZengInstitute of Paleobiology PASActa Palaeontologica Polonica0567-79201732-24212022-03-0167123925610.4202/app.00907.2021Ungulates of the middle Miocene Monarch Mill Formation, Churchill County, Nevada, USAKENT S. SMITH0NICHOLAS J. CZAPLEWSKI1MARGERY C. COOMBS2Office of American Indians in Medicine and Science and Department of Anatomy and Cell Biology, Oklahoma State University Center for Health Sciences, 1111 W 17th St., Tulsa, OK 74107 USASam Noble Museum, 2401 Chautauqua Ave., Norman, OK 73072 USADepartment of Biology, University of Massachusetts, Amherst, MA 01003 USA.A middle Miocene, early Barstovian land mammal age vertebrate assemblage, the Eastgate local fauna (LF), is known in the basal-most part of the Monarch Mill Formation. This rich assemblage of fossil vertebrates occurs within the Middlegate Basin in Churchill County, Nevada, USA. The Eastgate LF includes the fossil remains of fish, amphibians, reptiles, birds, and over 25 families of mammals. Previous studies on the mammalian remains have revealed several endemic taxa of rodents and carnivores. Herein, we describe the ungulates, which include two taxa from two families of Artiodactyla (Ticholeptus sp., Merycoidodontidae and Barbouromeryx trigonocorneus, Palaeomerycidae) and three taxa from three families of Perissodactyla (Equidae gen. et sp. indet., Moropus merriami, Chalicotheriidae, and Teleoceras sp., Rhinocerotidae). Independent paleobotanical evidence nearly contemporaneous with the vertebrates indicates forest and shrubland paleovegetation, and suggests that the area had been uplifted to 2700–2800 m paleoaltitude. Therefore, this local fauna adds a rare glimpse of a medium-to high-altitude vertebrate community in the intermountain western interior of North America. Temporally-restricted taxa (especially the rodent Tardontia nevadans and chalicothere Moropus merriami) reinforce the early Barstovian age of the Eastgate LF and are consistent with tephrochronological dates and radiometric analyses. The presence of Barbouromeryx trigonocorneus at Eastgate is significant in that its occurrence potentially represents a temporal range extension into the early Barstovian (previously known from latest Arikareean to middle Hemingfordian), and extends the paleobiogeographic range from the Great Plains to the Great Basin. Unequivocally, the ungulates and other mammals of the Eastgate LF support the presence of a temperate forest ecosystem in the Great Basin just subsequent to the Miocene Climatic Optimum.https://www.app.pan.pl/archive/published/app67/app009072021.pdfmammaliaungulatapaleoecologypalaeoclimatebarstovianmiocenemiddlegate basinnevada |
| spellingShingle | KENT S. SMITH NICHOLAS J. CZAPLEWSKI MARGERY C. COOMBS Ungulates of the middle Miocene Monarch Mill Formation, Churchill County, Nevada, USA Acta Palaeontologica Polonica mammalia ungulata paleoecology palaeoclimate barstovian miocene middlegate basin nevada |
| title | Ungulates of the middle Miocene Monarch Mill Formation, Churchill County, Nevada, USA |
| title_full | Ungulates of the middle Miocene Monarch Mill Formation, Churchill County, Nevada, USA |
| title_fullStr | Ungulates of the middle Miocene Monarch Mill Formation, Churchill County, Nevada, USA |
| title_full_unstemmed | Ungulates of the middle Miocene Monarch Mill Formation, Churchill County, Nevada, USA |
| title_short | Ungulates of the middle Miocene Monarch Mill Formation, Churchill County, Nevada, USA |
| title_sort | ungulates of the middle miocene monarch mill formation churchill county nevada usa |
| topic | mammalia ungulata paleoecology palaeoclimate barstovian miocene middlegate basin nevada |
| url | https://www.app.pan.pl/archive/published/app67/app009072021.pdf |
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