Understanding the Evolution and Clade Diversity of Mayorella (Amoebozoa): Description of a Novel Species From Freshwater Near Cape Coast, Ghana.

Mayorella species are globally distributed amoeboid protists, yet their diversity remains poorly resolved because of pronounced morphological plasticity and limited molecular data. Freshwater ecosystems of West Africa remain particularly underexplored, with virtually no integrative taxonomic or molecular studies addressing Mayorella and broader microbial eukaryotic diversity. Here, we describe Mayorella budamensis sp. nov. isolated from Budamu Stream, Ghana, using an integrative approach combining live-cell morphology and SSU rDNA phylogenetic analyses. The new species exhibits extensive morphological variation in cell size, shape, locomotion, and floating forms. Phylogenetic analyses place it within a well-supported lineage clustering with geographically diverse but largely unnamed and uncultured lineages. Comparative sequence analyses indicate that M. budamensis is genetically distinct from currently available congeners. A second Mayorella isolate recovered from the same locality, known only from single-cell-derived molecular data, represents an additional evolutionary lineage lacking a cultured isolate and currently associated primarily with environmental sequences. Expanded phylogenetic reconstruction identified up to seven putative clades, most containing unnamed or environmental taxa, revealing substantial cryptic diversity. These findings expand the known geographic and evolutionary diversity of Mayorella in African freshwater ecosystems and provide a provisional framework for future taxonomic and phylogenomic studies.