Biodiversity of groundwater fauna and water quality of some wells in the Zagora area, Morocco

This study investigates the Zagora aquifer, the main water resource in southeastern Morocco, between December 2020 and November 2021, with the aim of assessing groundwater invertebrate diversity and its relationship with water quality. Monthly sampling from nine wells combined physico-chemical analyses with detailed faunal identification. In total, 108 samples yielded 80 taxa, including Gastropoda, Oligochaeta, Ostracoda, Copepoda, Isopoda, Amphipoda, and Insecta, with five stygobiont taxa recorded. Multivariate analyses revealed significant differences between wells, but water quality was not the main driver of faunal distribution. Protected wells, less exposed to pollution, were dominated by dipterans (Chironomidae, Culicidae). Importantly, subterranean crustaceans belonging to Metacrangonyx, Monodella, Magnezia, and Typhlocirolana were identified for the first time in this aquifer. These findings highlight the biodiversity of the Zagora groundwater ecosystem and contribute novel records for Morocco’s subterranean fauna.