David Frey raised the hypothesis of non-cosmopolitanism in Cladocera in a series of his publications (Frey 1982, 1987). Since then, researchers have taken the effort to revise species groups with wide geographic distribution around the world (e.g. Kotov Dumont 2000; Sinev 2015; Van Damme Dumont 2008a; Sinev Elmoor-Loureiro 2009). The polyphyletic nature of the genus Alona Baird, 1843 (Van Damme et al. 2010) has further substantiated the view that cladocerans are non-cosmopolitan, with the creation of many new genera to accommodate the several species groups known within this genus (Van Damme Dumont 2008b; Sinev Kobayashi 2012; Van Damme Dumont 2009; Alonso Sinev 2019).
Keywords: Cladocera, Chydoridae, Aloninae.