Mesocyclops ogunnus (Cyclopoida) distribution across freshwater ecosystems worldwide: a systematic review of an exotic species

Mesocyclops ogunnus is a widespread copepod considered exotic in several regions worldwide. We conducted a systematic review to synthesize its global distribution, habitat preferences, research trends, and environmental associations. We extracted information from 97 articles published between 1992 and 2024 and indexed in Web of Science, Scopus, SciELO, and Google Scholar. We used generalized linear models to evaluate relationships between environmental conditions (temperature and trophic status), species abundance, and publication patterns. Most studies adopted a predictive design and were conducted in reservoirs and eutrophic environments. Publication frequency was not associated with temperature or year, and M. ogunnus abundance was not significantly associated with temperature or trophic state. The species was predominantly reported outside its native Afro-Asian range in warm, eutrophic, lentic ecosystems, which potentially favor its establishment and spread. Our synthesis highlights a broad biogeographic expansion of M. ogunnus and suggests that eutrophication and rising temperatures may increase freshwater ecosystems' vulnerability to future invasions. These findings advance understanding of invasion risk and support management strategies for exotic zooplankton species.