Eolian environments provide valuable information about arid climate intervals, yet the preservation of fossil bone microstructure, which can provide evidence of past environmental conditions in these settings, remains poorly understood. During the Last Glacial Maximum (LGM), eolian systems were more widespread than today across both hemispheres. In order to identify patterns associated with this type of environment, a series of LGM fossil specimens was selected from central Argentina, an area mantled by widespread eolian deposits. A combination of petrographic and scanning electron microscopy observations was employed, along with mineralogical (X-ray diffraction, XRD) and elemental chemical composition (energy-dispersive spectroscopy, EDS) analyses. Histological analysis revealed extensive bacterial bioerosion with superimposed generations, as well as radial and central microcracks, suggesting periodic environmental fluctuations. Mineral infillings, primarily carbonates and iron oxides, further reflect episodic changes in water availability over time. These taphonomic features support the interpretation of a depositional environment consistent with an interdune context characterized by alternating wet and dry conditions. The observed microstructural modifications highlight the relevance of histotaphonomic proxies for reconstructing environmental conditions in fossil-bearing eolian deposits and provide a comparative framework for similar deposits worldwide.