<p>We investigated the impact of forest fires on species richness and β-diversity of a zooplankton resting egg bank in a high-altitude temporary pond in the Neotropical region. We hypothesized that (i) species richness and (ii) total β-diversity (β_total) would be higher before forest fires than during and after fire; (iii) β_total would be driven by species replacement (β_repl) before and after fires; and (iv) during fires, β_total would be mainly driven by richness differences (β_rich). We used historical data from studies conducted in the same pond in 2014 and 2018 (i.e., before the fires), together with experimental hatching simulations during (2024) and after (2025) fire. Zooplankton species richness was higher before the fires. However, total β-diversity was highest during the fire period and was driven by richness differences, revealing a marked loss of species. Our findings indicate that forest fires acted as an environmental filter, reducing zooplankton viability and diversity and promoting species loss, thereby highlighting the negative effects of forest fire events and their implications for the future structure of communities. Predicted scenarios of increasing temperatures and higher fire frequency in tropical regions may modulate the establishment and selection of zooplankton species in temporary aquatic ecosystems.</p>