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Abstract Based on previously published molecular (mitochondrial) and herein provided morphological (qualitative and quantitative data) evidence, we describe a new species of leaf-eared mouse of the genus Phyllotis . The new species is morphometrically distinct when compared with other phylogenetically or geographically close species of Phyllotis , showing several quantitative differences in their external and craniodental characters (e.g., proportionally broader nasals and interorbital region, and proportionally smaller tympanic bullae). The new species is endemic to central Argentina, occurring on rocky grasslands at elevations of 650–2,800 m a.s.l. This is the only species of Phyllotis inhabiting the Central Sierras, a mountain system of medium elevation, isolated from the Andes by low elevation arid and semiarid environments.
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Evidence of a population of leaf-eared mice Phyllotis vaccarum above 6,000 m in the Andes and a survey of high-elevation mammals
Abstract Biologists have long pondered the extreme limits of life on Earth, including the maximum elevation at which species can live and reproduce. Here we review evidence of a self-sustaining population of mice at an elevation that exceeds that of all previously reported for mammals. Five expeditions over 10 years to Volcán Llullaillaco on the Argentina/Chile border observed and collected mice at elevations ranging from 5,070 m at the mountain’s base to the summit at 6,739 m (22,110 feet). Previously unreported evidence includes observations and photographs of live animals and mummified remains, environmental DNA, and a soil microbial community reflecting animal activity that are evaluated in combination with previously reported video recordings and capture of live mice. All of the evidence identifies the mouse as the leaf-eared mouse Phyllotis vaccarum, and it robustly places the population within a haplotype group containing individuals from the Chilean Atacama Desert and nearby regions of Argentina. A critical review of the literature affirms that this population is not only an elevational record for mammals but for all terrestrial vertebrates to date, and we further find that many extreme elevations previously reported for mammals are based on scant or dubious evidence.
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- PAR ID:
- 10371182
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Journal of Mammalogy
- Volume:
- 103
- Issue:
- 4
- ISSN:
- 0022-2372
- Format(s):
- Medium: X Size: p. 776-785
- Size(s):
- p. 776-785
- Sponsoring Org:
- National Science Foundation
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