A new freshwater amoeba from Ghana points to hidden species diversity

Mayorella budamensis was found in a stream near Cape Coast, alongside another lineage known only from DNA data.

Editorial illustration — not from the study.

The new species, Mayorella budamensis, was identified using observations of living cells and comparisons of small-subunit ribosomal DNA, a genetic marker used to study relationships among organisms. The amoeba showed wide variation in cell size, shape, movement and floating forms, but its DNA distinguished it from the Mayorella species currently represented in sequence databases.

A second Mayorella isolate from the same stream formed another evolutionary lineage, although it was represented only by molecular data from a single cell and was not cultured. Broader analyses placed Mayorella into up to seven putative groups, most of which included unnamed or environmental lineages.

New amoeba lineages

The researchers formally described Mayorella budamensis sp. nov. from freshwater near Cape Coast, Ghana. The species has substantial variation in cell size, shape, locomotion and floating forms, and its small-subunit ribosomal DNA places it in a well-supported lineage with geographically diverse but mostly unnamed or uncultured organisms. Comparative sequence analysis indicates that it is genetically distinct from the Mayorella species currently available for comparison.

The same locality yielded a second Mayorella lineage known only from single-cell molecular data; no cultured isolate is available. An expanded evolutionary analysis identified up to seven putative Mayorella clades, most containing unnamed or environmental taxa.

Why Ghana’s stream matters

Freshwater ecosystems in West Africa have received little integrative taxonomic or molecular study, including research on Mayorella and other microbial eukaryotes. The findings add a formally described species from an understudied region and show that Mayorella diversity includes multiple lineages that have not yet been named or cultured. The study provides a provisional framework for future taxonomic and genome-scale evolutionary research.

Evidence and open questions

The study combines observations of living-cell morphology with small-subunit ribosomal DNA phylogenetic analyses, an approach that uses both physical characteristics and genetic relationships. The conclusions about M. budamensis are based on one described species from Budamu Stream, while the second lineage is known only from molecular data from a single cell and lacks a cultured isolate. The reported groups are described as putative clades, and the abstract does not provide broader sampling details or genome-scale data, so the full diversity and relationships of Mayorella remain unresolved.

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