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Abstract The fossil record of treeshrews, hedgehogs, and other micromammals from the Lower Siwaliks of India is sparse. Here, we report on a new genus and species of fossil treeshrew, specimens of the hedgehog Galerix , and other micromammals from the middle Miocene (Lower Siwalik) deposits surrounding Ramnagar (Udhampur District, Jammu and Kashmir), at a fossil locality known as Dehari. The treeshrew from Dehari ( Sivatupaia ramnagarensis n. gen. n. sp.) currently represents the oldest record of fossil tupaiids in the Siwaliks, extending their time range by ca. 2.5–4.0 Myr in the region. Dietary analyses suggest that the new tupaiid was likely adapted for a less mechanically challenging or more frugivorous diet compared to other extant and fossil tupaiids. The occurrence of Galerix has only been recently documented from the Indian Siwaliks and the Dehari specimens help establish the likely presence of a relatively large Siwalik Galerix species in the Ramnagar region. In addition to the new treeshrew and hedgehogs, new specimens of the rodents Kanisamys indicus , Sayimys sivalensis , and Murinae indet. from Dehari help confirm that age estimates for the Ramnagar region are equivalent to the Chinji Formation in Pakistan, most likely corresponding to the middle to upper part of the Chinji Formation. UUID: http://zoobank.org/56fb160c-2df8-4cd3-be91-af4dc02d0979
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First report of rodents from the Miocene Siwalik locality of Dunera, Pathankot District, Punjab, India
Although there have been a few reports of macromammals from the Siwalik site of Dunera, no micromammals have yet been described. Recently, a diverse micromammal fossil assemblage represented by isolated teeth has been recovered from Dunera. The specimens are identified as a murine similar to Progonomys hussaini (Progonomys cf. hussaini), the ctenodactylid Sayimys sivalensis, the cricetid Democricetodon fejfari, and a sciurid, cf. Tamias urialis. These rodents are documented for the first time from this region of the Indian Siwaliks. Based on the biostratigraphic ranges of these rodents from well-dated localities in the Siwaliks of Pakistan along with previously collected magnetostratigraphic data, Dunera locality best correlates to between ~11-10 Ma (early Late Miocene), approximately equivalent to the lower half of the Nagri Formation. Previous magneto-stratigraphic data suggests that an age closer to ~11 Ma is more likely, perhaps sampling a temporal gap in the known Siwaliks micromammal record and extending the age ranges of P. hussaini and T. urialis by a few hundred thousand years.
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- PAR ID:
- 10526336
- Publisher / Repository:
- Palaeontologia Electronica
- Date Published:
- Journal Name:
- Palaeontologia Electronica
- ISSN:
- 1935-3952
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.26879/1308
