Abstract: Glaciers in High Mountain Asia, despite their vast extent, harbor poorly understood biodiversity compared to other mountain ranges. This study describes a new species of springtail, Desoria passui sp. n., and reports chironomid found as larva from the Passu Glacier in the Pakistani Karakoram. Phylogenetic analyses reveal that D. passui sp. n. is genetically distinct from known cryophilic springtails in European mountain ranges, indicating a local evolutionary lineage. Similarly, the chironomid larvae represent a potentially undescribed species within Metriocnemus that does not form a sister group but is instead affiliated also with other barcoded Eurasian species associated with glacial habitats. These findings suggest that the cryophilic arthropod diversity of the Karakoram remains largely undocumented and their evolutionary history is independent of other known mountain cryophilic species. Given the ongoing glacier retreat, documenting and understanding this hidden biodiversity are critical for informing conservation strategies and assessing ecosystem responses to climate change.

Key words: Collembola, cryophilic, Diptera Chironomidae, Karakoram glacier, new species discovery