| Species |
Recipient region |
Date of the first record |
|
| Asparagopsis armata | Italy / Central Mediterranean | To 1972 |  |
| Asparagopsis armata | Italy / Western Mediterranean | To 1955 | |
| Asparagopsis armata | Netherlands | To 1983 | |
| Asparagopsis armata | Portugal / Azores | 1989 | |
| Asparagopsis armata | Portugal / Iberian Coastal | 1951 | |
| Asparagopsis armata | Portugal / Madeira | To 1974 | |
| Asparagopsis armata | Spain / Canary Islands | To 1980 | |
| Asparagopsis armata | Spain / Iberian Coastal | 1933 | |
| Asparagopsis armata | Turkey / Black Sea | 1973 | |
| Asparagopsis armata | United Kingdom (Britain) / Celtic seas / Channel Islands | 1949 | |
| Asparagopsis armata | United Kingdom (Britain) / English Channel | 1949 - 1950 | |
| Asparagopsis armata | United Kingdom (Britain) / North Sea | 1973 | |
| Asparagopsis armata | United Kingdom (Britain) / North Sea / Orkney Islands | From 1960 | |
| Asparagopsis taxiformis | France / Western Mediterranean | To 2006 | |
| Asparagopsis taxiformis | Portugal / Azores | 1929 | |
| Asparagopsis taxiformis | Portugal / Iberian Coastal | To 2000 | |
| Asparagopsis taxiformis | Portugal / Madeira | 1970 | |
| Asparagopsis taxiformis lineage 2 | Greece / Adriatic Sea | 2013 | |
| Asparagopsis taxiformis lineage 2 | Greece / Central Mediterranean | 2006 | |
| Asparagopsis taxiformis lineage 2 | Greece / Eastern Mediterranean | 1992 | |
| Asparagopsis taxiformis lineage 2 | Italy / Central Mediterranean | 1992 | |
| Asparagopsis taxiformis lineage 2 | Italy / Western Mediterranean | 1993 | |
| Asperococcus ensiformis | Australia / Bass strait | 1976 | |
| Asperococcus scaber | Netherlands | 1998 | |
| Aspidosiphon mexicanus | Greece / Central Mediterranean | 1994 | |
| Aspidosiphon mexicanus | Greece / Eastern Mediterranean | 1991 | |
| Asterias amurensis | Australia / Bass strait | 1995 | |
| Asterias rubens | Turkey / Black Sea | 2003 | |
| Asterionellopsis glacialis | Netherlands | To 2018 | |
| Asterionellopsis glacialis | Romania | 1968 | |
| Asterionellopsis glacialis | Russia / Black Sea | 1998 | |
| Asterionellopsis glacialis | Ukraine / Black Sea | From 1967 | |
| Asterocarpa humilis | France / Biscay Gulf | To 2013 | |
| Asterocarpa humilis | France / English Channel | 2005 | |
| Asterocarpa humilis | United Kingdom (Britain) / Celtic seas | 2013 | |
| Asterocarpa humilis | United Kingdom (Britain) / North Sea / Orkney Islands | 2014 | |
| Asteromphalus sarcophagus | France / Biscay Gulf | To 2003 | |
| Asteromphalus sarcophagus | France / Celtic seas | 2003 | |
| Asteromphalus sarcophagus | France / English Channel | 2001 | |
| Asthenognathus atlanticus | France / English Channel | 2008 | |
| Asthenognathus atlanticus | Netherlands | 2019 | |
| Atergatis roseus | Greece / Eastern Mediterranean | 2009 | |
| Atergatis roseus | Israel | 1961 | |
| Atherina boyeri | Netherlands | To 1964 | |
| Atherina boyeri | United Kingdom (Britain) / Celtic seas | 1956 | |
| Atherinomorus forskalii | Greece / Central Mediterranean | 2012 | |
| Atherinomorus forskalii | Greece / Eastern Mediterranean | 1986 | |
| Atherinomorus forskalii | Israel | 1924 | |
| Atrina rigida | United Kingdom (Britain) / English Channel | 1986 | |
| Attheya armata | United Kingdom (Britain) / Celtic seas | 2000 | |
