<br> During a Chiroptera resource survey conducted in 2023 on the Pamir Plateau of China’s Xinjiang Uygur Autonomous Region, two adult male bat individuals were captured. External morphology examination revealed small-sized individuals characterized by long, narrow ears with straight tragus structures tapering to sharp tips—features diagnostic of the genus<br> Myotis<br> . Concurrently, we obtained free-flight echolocation calls from the bats: the signals showed an initial frequency of 65.12 ± 2.12 kHz, terminal frequency of 42.78 ± 1.27 kHz, peak energy frequency of 47.41 ± 1.46 kHz, pulse duration of 2.52 ± 0.26 ms, and inter-pulse interval of 94.01 ± 31.41 ms. Based on skull morphological traits and bioacoustic data, the specimens were preliminarily identified as<br> Myotis aurascens<br> . However, our phylogenetic analysis based on the mitochondrial cytochrome<br> b<br> (<br> Cytb<br> ) gene revealed that sequences attributed to<br> M. aurascens<br> and<br> M. davidii<br> formed a single strongly supported clade, underscoring the unresolved taxonomic status of these species. Irrespective of the exact species assignment, this discovery constitutes the first documented occurrence of the<br> M. davidii<br> /<br> aurascens<br> complex on the Pamir Plateau, thereby extending the known distribution range in China. Notably, these specimens represent the highest-elevation record for this group to date (3200 m). Our study provides the first comprehensive description of cranial morphology and echolocation signatures for this taxon in a high-altitude habitat. These findings significantly enhance regional biodiversity inventories and offer critical baseline data for plateau ecosystem research.<br>
