| Species |
Recipient region |
Date of the first record |
|
| Kaloplocamus ramosus | Australia / Bass strait | To 1950 |  |
| Kapraunia schneideri | Italy / Adriatic Sea | 2016 | |
| Karenia brevisulcata | France / Biscay Gulf | 2009 | |
| Karenia mikimotoi | Denmark / Baltic Sea | 1968 | |
| Karenia mikimotoi | Denmark / North Sea | 1968 | |
| Karenia mikimotoi | France / Biscay Gulf | To 1985 | |
| Karenia mikimotoi | France / Celtic seas | 1976 | |
| Karenia mikimotoi | France / English Channel | 1976 | |
| Karenia mikimotoi | France / North Sea | 1989 | |
| Karenia mikimotoi | France / Western Mediterranean | To 1985 | |
| Karenia mikimotoi | Germany / Baltic Sea | 1981 - 1989 | |
| Karenia mikimotoi | Germany / North Sea | 1968 | |
| Karenia mikimotoi | Greece / Eastern Mediterranean | 1989 | |
| Karenia mikimotoi | Ireland | 1976 | |
| Karenia mikimotoi | Netherlands | 1989 | |
| Karenia mikimotoi | Norway / North Sea | To 1966 | |
| Karenia mikimotoi | Portugal / Iberian Coastal | To 2007 | |
| Karenia mikimotoi | Spain / Iberian Coastal | To 2006 | |
| Karenia mikimotoi | Sweden / Baltic Sea | 1980 - 1987 | |
| Karenia mikimotoi | Sweden / North Sea | 1981 | |
| Karenia mikimotoi | United Kingdom (Britain) / Celtic seas | 1971 | |
| Karenia mikimotoi | United Kingdom (Britain) / English Channel | 1971 | |
| Karenia mikimotoi | United Kingdom (Britain) / North Sea | 2006 | |
| Karenia mikimotoi | United Kingdom (Britain) / North Sea / Orkney Islands | To 2006 | |
| Karenia papilionacea | France / Biscay Gulf | 1994 | |
| Karenia papilionacea | France / Celtic seas | 1994 | |
| Karenia papilionacea | France / English Channel | 1994 | |
| Karenia umbella | France / Biscay Gulf | 2008 | |
| Karenia umbella | France / English Channel | 2008 | |
| Karlodinium decipiens | France / Biscay Gulf | 2009 | |
| Karlodinium decipiens | France / English Channel | 2010 | |
| Karlodinium veneficum | Germany / North Sea | To 2009 | |
| Karlodinium veneficum | Norway / North Sea | To 2002 | |
| Kellicottia bostoniensis | Poland | 2022 | |
| Kirchenpaueria halecioides | Portugal / Azores | To 1989 | |
| Kirchenpaueria halecioides | Portugal / Madeira | 1980 | |
| Koinostylochus ostreophagus | France / Biscay Gulf | 1970 - 1979 | |
| Koinostylochus ostreophagus | France / Celtic seas | 1979 | |
| Koinostylochus ostreophagus | France / English Channel | 1970 | |
| Kuckuckia spinosa | Australia / Bass strait | 1971 | |
| Kyphosus sectatrix | France / Western Mediterranean | 2006 | |
