| Main Ref. | Bartley, D.M. (comp./ed.), 2006 |
| To | Netherlands |
| FAO area | Atlantic, Northeast |
| From | Japan |
| FAO area | |
| Year | 2000 |
| Range | |
| Period | 1975-present |
| Established in the Wild | yes, self reproducing |
| Established in Aquaculture | |
| Significant Ecological Interactions | probably yes - adverse |
| Significant Socio-economic Effects | |
| Introduced by | unknown |
| Reason | diffused from other countries |
| Other Reason | accidental |
| Comments | first discovered in France in 1994. Hull fouling. Densities of infestations can be as high as 20 specimens/m2. effect on other rocky shore organisms through predation and other competitive interactions. |