Diadumene cincta is a small sea anemone (family Diadumenidae) native to the North Pacific but widely introduced into harbors and bays worldwide, becoming an established invasive species in temperate Atlantic and European waters by rapidly colonizing artificial substrates such as pilings, boat hulls, and mussel beds through asexual laceration. Its small body size, rapid reproduction, and broad salinity and temperature tolerance make it one of the most successful marine invasive invertebrates globally. Genomic data have been generated for this species and are available in public databases, enabling comparative studies of cnidarian evolution and ecology.