| Main Ref. | Ashelby, C.W., S. De Grave and M.L. Johnson, 2013 |
| To | Gent-Terneuzen Canal |
| FAO area | Europe - Inland waters |
| From | UK |
| FAO area | |
| Year | 1998 |
| Range | |
| Period | 1975-present |
| Established in the Wild | |
| Established in Aquaculture | |
| Significant Ecological Interactions | |
| Significant Socio-economic Effects | |
| Introduced by | |
| Reason | diffused from other countries |
| Other Reason | accidental with ships |
| Comments | Initially recorded in 1998 from the Gent-Terneuzen Canal near Gen Harbour in low numbers, P. macrodactylus numbers increased dramatically by 2003. With the U.K. being postulated as the primary entry point to Europe, the population in Belgium could have resulted from either natural diffusion or from shipping traffic. |