Global Distribution and Variation of the Invasive Cheilostome Bryozoan .

Viable populations of the cheilostome bryozoan Ito, Onishi & Dick exist in the NW Pacific (Russian Far East and northern Japan), NE Atlantic (Scandinavia and Scotland), and NW Atlantic (Maine, USA). The first NE and NW Atlantic records are from Norway (2008) and Casco Bay, Maine, USA (2018), respectively, indicating a relatively recent introduction to the region. Mitochondrial COI gene sequences from North Atlantic populations (Sweden, Norway, and Maine) showed two haplotypes differing by one substitution, but differed from two haplotypes from Akkeshi, northern Japan, by 6-8 substitutions.