The draft genome of the calcareous foraminifera Ammonia Veneta (rotaliida, globothalamea, foraminifera)

Foraminifera are abundant and widely spread protists that contribute to global biogeochemical cycles and are used as bioindicators of polluted environments. However, their genomic basis remains poorly understood due to technical difficulties such as high genome complexity, microbial contamination, and the lack of axenic cultures. Here, we present the first draft genome of an axenic strain of a benthic foraminifer, Ammonia veneta WYF01. The 433 Mb genome assembly exhibits high completeness (80 % BUSCO score) and reveals a complex genomic landscape with extensive repeat content and 350,650 predicted gene models. Comparative genomic analysis with other rhizarians highlights conserved gene families related to pseudopodial motility and some osmoregulation, and substrate adhesion as species-specific expansions in A. veneta . Notably, we observed remarkable diversification of glutathione S-transferase genes, involved in detoxification of reactive oxygen species and xenobiotics, suggesting a genomic basis for this species' tolerance to polluted environments. Our findings provide valuable insights into the molecular adaptations of benthic Foraminifera and establish A. veneta as a genomic model for future evolutionary and environmental studies. • We present the first draft genome of a foraminifer strain Ammonia veneta WYF01. • Genome completeness is the highest reported among foraminiferal genomes to date. • Comparative genomics clarifies core gene conservation across Rhizaria lineages. • Genomic data offer new insights into cellular adaptation and foraminiferal evolution. • Lineage-specifically expanded gst genes show foraminiferal tolerance to pollution.