| Species |
Recipient region |
Date of the first record |
|
| Babka gymnotrachelus | Poland | 2021 |  |
| Bacteriastrum hyalinum | Bulgaria | 1907 | |
| Bacteriastrum hyalinum | Denmark / Baltic Sea | 1983 | |
| Bacteriastrum hyalinum | Denmark / North Sea | 1983 | |
| Bacteriastrum hyalinum | Romania | 1907 | |
| Bacteriastrum hyalinum | Ukraine / Black Sea | From 1907 | |
| Balanus amphitrite | Australia / Bass strait | To 1999 | |
| Balanus amphitrite | Belgium | 1952 | |
| Balanus amphitrite | France / Biscay Gulf | 1914 | |
| Balanus amphitrite | France / Celtic seas | 1914 | |
| Balanus amphitrite | Germany / North Sea | 2002 | |
| Balanus amphitrite | Ireland | To 1986 | |
| Balanus amphitrite | Netherlands | 1962 | |
| Balanus amphitrite | Portugal / Iberian Coastal | To 1854 | |
| Balanus amphitrite | Spain / Iberian Coastal | 1934 | |
| Balanus amphitrite | Sweden / North Sea | | |
| Balanus amphitrite | Ukraine / Black Sea | From 1905 | |
| Balanus amphitrite | United Kingdom (Britain) / English Channel | From 1937 | |
| Balanus glandula | Belgium | 2015 | |
| Balanus trigonus | Belgium | 1997 | |
| Balanus trigonus | France / Biscay Gulf | 2007 | |
| Balanus trigonus | France / Celtic seas | To 2007 | |
| Balanus trigonus | France / English Channel | 2007 | |
| Balanus trigonus | Greece / Eastern Mediterranean | 1970 | |
| Balanus trigonus | Italy / Adriatic Sea | 1964 | |
| Balanus trigonus | Italy / Central Mediterranean | To 1927 | |
| Balanus trigonus | Italy / Western Mediterranean | To 1962 | |
| Balanus trigonus | Portugal / Azores | To 1887 | |
| Balanus trigonus | Portugal / Iberian Coastal | To 2013 | |
| Balanus trigonus | Portugal / Madeira | To 1916 | |
| Balanus trigonus | Spain / Iberian Coastal | To 2007 | |
| Balanus trigonus | United Kingdom (Britain) / English Channel | 1986 | |
| Bangia atropurpurea | Australia / Bass strait | 1971 | |
| Bankia carinata | Greece / Eastern Mediterranean | 2008 - 2013 | |
| Bankia fimbriatula | Ireland | 1847 | |
| Barentsia benedeni | Germany / Baltic Sea | 2016 - 2021 | |
| Barentsia benedeni | Germany / North Sea | 2021 | |
| Barentsia benedeni | Russia / Caspian Sea | 1962 | |
| Barentsia matsushimana | Germany / North Sea | 2021 | |
| Barentsia ramosa | Netherlands | 2003 | |
| Beania maxilladentata | Portugal / Madeira | To 2013 | |
| Beania mirabilis | Spain / Canary Islands | To 2003 | |
| Bedeva paivae | Portugal / Madeira | To 1994 | |
| Bedeva paivae | Spain / Canary Islands | To 2003 | |
| Bellamya chinensis | Netherlands | 2009 | |
| Belzebub hanseni | Israel | 2008 | |
| Bemlos leptocheirus | Greece / Eastern Mediterranean | 2015 | |
| Bemlos leptocheirus | Israel | 2009 | |
| Beroe cucumis | Turkey / Black Sea | From 1992 | |
| Beroe ovata | Bulgaria | 1997 | |
| Beroe ovata | Denmark / Baltic Sea | 2011 | |
| Beroe ovata | Denmark / North Sea | 2013 | |
| Beroe ovata | Georgia | 1996 | |
| Beroe ovata | Greece / Eastern Mediterranean | 2004 | |
| Beroe ovata | Israel | 2011 | |
| Beroe ovata | Italy / Adriatic Sea | 2005 | |
| Beroe ovata | Romania | 1996 | |
| Beroe ovata | Russia / Black Sea | 1999 | |
| Beroe ovata | Sweden / North Sea | 2019 | |
| Beroe ovata | Turkey / Black Sea | 1996 | |
| Beroe ovata | Ukraine / Azov Sea | From 1997 | |
| Beroe ovata | Ukraine / Black Sea | From 1997 | |
| Berthellina citrina | Israel | 1956 | |
| Beryx splendens | France / Western Mediterranean | 1992 | |
| Biflustra grandicella | Netherlands | 2016 | |
| Bispira fabricii | France / English Channel | 2010 | |
| Bispira polyomma | Italy / Adriatic Sea | 2014 | |
| Bispira polyomma | Netherlands | To 2010 | |
| Biuve fulvipunctata | Israel | 1986 | |
| Biuve fulvipunctata | Italy / Central Mediterranean | 2015 | |
| Bivetiella cancellata | Spain / Iberian Coastal | 1999 | |
| Blackfordia virginica | Bulgaria | 1925 | |
| Blackfordia virginica | France / Biscay Gulf | 1953 | |
| Blackfordia virginica | France / Celtic seas | 1971 | |
| Blackfordia virginica | France / English Channel | 1973 | |
| Blackfordia virginica | Germany / Baltic Sea | 2014 | |
| Blackfordia virginica | Iran / Caspian Sea | From 1956 | |
| Blackfordia virginica | Netherlands | 2014 | |
| Blackfordia virginica | Portugal / Iberian Coastal | 1984 | |
| Blackfordia virginica | Romania | 1940 | |
| Blackfordia virginica | Russia / Azov Sea | 1930 | |
| Blackfordia virginica | Spain / Iberian Coastal | To 2008 | |
| Blackfordia virginica | Ukraine / Black Sea | 1960 - 1969 | |
| Boccardia polybranchia | France / Biscay Gulf | 1900 | |
| Boccardia polybranchia | France / Celtic seas | 2004 | |
| Boccardia polybranchia | France / English Channel | 1893 | |
| Boccardia polybranchia | France / North Sea | 1893 | |
| Boccardia proboscidea | Australia / Bass strait | 1978 | |
| Boccardia proboscidea | Belgium | To 2011 | |
| Boccardia proboscidea | France / Biscay Gulf | 2013 | |
| Boccardia proboscidea | France / English Channel | 1999 | |
| Boccardia proboscidea | France / North Sea | 2014 | |
| Boccardia proboscidea | Germany / North Sea | 2008 | |
| Boccardia proboscidea | Netherlands | 2013 | |
| Boccardia proboscidea | Spain / Iberian Coastal | 1996 | |
| Boccardia proboscidea | United Kingdom (Britain) / North Sea / Orkney Islands | 2014 | |
| Boccardia pseudonatrix | France / English Channel | 2018 | |
| Boccardia semibranchiata | France / Biscay Gulf | 1999 | |
| Boccardia semibranchiata | France / Celtic seas | 1999 | |
| Boccardia semibranchiata | France / English Channel | 1999 | |
| Boccardia semibranchiata | France / North Sea | 1999 | |
| Boccardia semibranchiata | Spain / Iberian Coastal | To 2003 | |
| Boccardiella hamata | Belgium | To 2018 | |
| Boccardiella hamata | France / English Channel | 2018 | |
| Boccardiella hamata | Germany / North Sea | 2021 | |
| Boccardiella hamata | Netherlands | To 2013 | |
| Boccardiella ligerica | Belgium | 1962 | |
| Boccardiella ligerica | Finland | 1960 - 1969 | |
| Boccardiella ligerica | France / English Channel | To 1960 | |
| Boccardiella ligerica | France / North Sea | To 1960 | |
| Boccardiella ligerica | Germany / Baltic Sea | 1932 | |
| Boccardiella ligerica | Germany / North Sea | To 2000 | |
| Boccardiella ligerica | Latvia | 2014 | |
| Boccardiella ligerica | Netherlands | To 1919 | |
| Boccardiella ligerica | Poland | 2017 | |
| Boccardiella ligerica | Sweden / Baltic Sea | 2013 | |
| Bolinopsis vitrea | Bulgaria | 2010 | |
| Bolinopsis vitrea | Turkey / Black Sea | 2007 | |
| Bonamia exitiosa | France / English Channel | 1981 | |
| Bonamia exitiosa | Spain / Iberian Coastal | 2007 | |
| Bonamia ostreae | Belgium | From 1979 | |
| Bonamia ostreae | Denmark / Baltic Sea | 2014 | |
| Bonamia ostreae | Denmark / North Sea | 2014 | |
| Bonamia ostreae | France / Biscay Gulf | 1979 | |
| Bonamia ostreae | France / Celtic seas | 1979 | |
| Bonamia ostreae | France / North Sea | 1981 | |
| Bonamia ostreae | France / Western Mediterranean | 1987 | |
| Bonamia ostreae | Ireland | To 1986 | |
| Bonamia ostreae | Netherlands | 1980 | |
| Bonamia ostreae | Spain / Iberian Coastal | 1982 | |
| Bonamia ostreae | United Kingdom (Britain) / Celtic seas / Channel Islands | From 1982 | |
| Bonamia ostreae | United Kingdom (Britain) / English Channel | 1982 | |
| Bonamia ostreae | United Kingdom (Britain) / North Sea | 1982 - 1983 | |
| Boninia neotethydis | Israel | 1998 | |
| Bonnemaisonia asparagoides | Turkey / Black Sea | 1990 - 1999 | |
| Bonnemaisonia hamifera | Belgium | To 1999 | |
| Bonnemaisonia hamifera | Denmark / Baltic Sea | 1900 | |
| Bonnemaisonia hamifera | Denmark / North Sea | 1900 | |
| Bonnemaisonia hamifera | Faroe Islands | 1980 | |
| Bonnemaisonia hamifera | France / Biscay Gulf | 1996 | |
| Bonnemaisonia hamifera | France / Celtic seas | 1898 | |
| Bonnemaisonia hamifera | France / English Channel | 1901 | |
| Bonnemaisonia hamifera | Germany / North Sea | 1890 - 1899 | |
| Bonnemaisonia hamifera | Iceland | 1978 | |
| Bonnemaisonia hamifera | Ireland | 1911 | |
| Bonnemaisonia hamifera | Italy / Adriatic Sea | 1995 | |
| Bonnemaisonia hamifera | Italy / Central Mediterranean | 1973 | |
| Bonnemaisonia hamifera | Netherlands | To 1983 | |
| Bonnemaisonia hamifera | Norway / Barents Sea | 1902 | |
| Bonnemaisonia hamifera | Norway / North Sea | 1902 | |
| Bonnemaisonia hamifera | Norway / Norwegian Sea | 1902 | |
| Bonnemaisonia hamifera | Portugal / Azores | 1989 | |
| Bonnemaisonia hamifera | Portugal / Iberian Coastal | 2003 - 2008 | |
| Bonnemaisonia hamifera | Spain / Canary Islands | To 1980 | |
| Bonnemaisonia hamifera | Spain / Iberian Coastal | To 2006 | |
| Bonnemaisonia hamifera | Sweden / North Sea | 1902 | |
| Bonnemaisonia hamifera | United Kingdom (Britain) / Celtic seas / Channel Islands | From 1890 | |
| Bonnemaisonia hamifera | United Kingdom (Britain) / English Channel | From 1890 | |
| Bonnemaisonia hamifera | United Kingdom (Britain) / North Sea | 1893 - 1986 | |
| Bonnemaisonia hamifera | United Kingdom (Britain) / North Sea / Orkney Islands | To 1960 | |
| Botrylloides anceps | Israel | 1991 | |
| Botrylloides diegensis | France / Biscay Gulf | 2007 | |
| Botrylloides diegensis | France / English Channel | 1999 | |
| Botrylloides diegensis | France / Western Mediterranean | 2012 | |
| Botrylloides diegensis | Italy / Adriatic Sea | 2015 | |
| Botrylloides giganteus | Italy / Central Mediterranean | 2003 | |
| Botrylloides leachii | Australia / Bass strait | 1901 | |
| Botrylloides leachii | Portugal / Madeira | 1993 | |
| Botrylloides leachii | Spain / Canary Islands | To 2003 | |
| Botrylloides leachii | United Kingdom (Britain) / North Sea / Orkney Islands | 1995 | |
| Botrylloides niger | Israel | 1952 | |
| Botrylloides niger | Portugal / Madeira | 2013 | |
| Botrylloides violaceus | Belgium | 2004 | |
| Botrylloides violaceus | Canada / Bay of Fundy | 2009 | |
| Botrylloides violaceus | Canada / Northern Gulf of St. Lawrence | 2014 | |
| Botrylloides violaceus | Canada / Northern Newfoundland | 2007 | |
| Botrylloides violaceus | Canada / South-eastern Scotian Shelf | 2001 | |
| Botrylloides violaceus | Canada / Southern Gulf of St. Lawrence and Eastern Scotian Shelf | 2004 | |
| Botrylloides violaceus | Canada / Southern Newfoundland and Southern Grand Banks | 2007 | |
| Botrylloides violaceus | France / Biscay Gulf | To 2000 | |
| Botrylloides violaceus | France / English Channel | 2000 | |
| Botrylloides violaceus | France / North Sea | 2004 | |
| Botrylloides violaceus | Germany / North Sea | 2011 | |
| Botrylloides violaceus | Iceland | 2018 | |
| Botrylloides violaceus | Ireland | 2005 | |
| Botrylloides violaceus | Italy / Adriatic Sea | 1993 | |
| Botrylloides violaceus | Netherlands | 2000 | |
| Botrylloides violaceus | Portugal / Iberian Coastal | From 2009 | |
| Botrylloides violaceus | Portugal / Madeira | 2007 | |
| Botrylloides violaceus | Spain / Iberian Coastal | To 2016 | |
| Botrylloides violaceus | United Kingdom (Britain) / Celtic seas / Channel Islands | From 2004 | |
| Botrylloides violaceus | United Kingdom (Britain) / English Channel | 2004 | |
| Botrylloides violaceus | United Kingdom (Britain) / North Sea / Orkney Islands | To 2012 | |
| Botryllus gaiae | Italy / Adriatic Sea | 2013 | |
| Botryllus gaiae | Italy / Central Mediterranean | 2013 | |
| Botryllus gaiae | Italy / Western Mediterranean | 2006 | |
| Botryllus schlosseri | Australia / Bass strait | 1977 | |
| Botryllus schlosseri | Canada / Bay of Fundy | 1970 - 1979 | |
| Botryllus schlosseri | Canada / Northern Gulf of St. Lawrence | 1975 | |
| Botryllus schlosseri | Canada / Northern Newfoundland | 2007 | |
| Botryllus schlosseri | Canada / South-eastern Scotian Shelf | 1950 - 1959 | |
| Botryllus schlosseri | Canada / Southern Gulf of St. Lawrence and Eastern Scotian Shelf | 2001 | |
| Botryllus schlosseri | Canada / Southern Newfoundland and Southern Grand Banks | 1940 - 1949 | |
| Botryllus schlosseri | Germany / Baltic Sea | To 2015 | |
| Botryllus schlosseri | Germany / North Sea | To 2016 | |
| Botryllus schlosseri | Greece / Eastern Mediterranean | 1955 | |
| Botryllus schlosseri | Iceland | 2011 | |
| Botryllus schlosseri | Italy / Adriatic Sea | To 2004 | |
| Botryllus schlosseri | Italy / Central Mediterranean | To 2011 | |
| Botryllus schlosseri | Italy / Western Mediterranean | To 2005 | |
| Botryllus schlosseri | Portugal / Azores | To 1971 | |
| Botryllus schlosseri | Portugal / Iberian Coastal | To 1970 | |
| Botryllus schlosseri | Portugal / Madeira | To 2006 | |
| Botryllus schlosseri | Spain / Canary Islands | To 2003 | |
| Botryllus schlosseri | United Kingdom (Britain) / North Sea / Orkney Islands | 1995 | |
| Botryocladia madagascariensis | Greece / Central Mediterranean | 2009 | |
| Botryocladia madagascariensis | Greece / Eastern Mediterranean | 2006 | |
| Botryocladia madagascariensis | Israel | 2014 | |
| Botryocladia madagascariensis | Italy / Adriatic Sea | 1997 | |
| Botryocladia madagascariensis | Italy / Central Mediterranean | 1991 | |
| Botryocladia wrightii | France / Biscay Gulf | 2010 | |
| Botryocladia wrightii | France / English Channel | 2019 | |
| Botryocladia wrightii | France / Western Mediterranean | 1978 | |
| Botrytella micromora | Australia / Bass strait | 1970 | |
| Botrytella parva | Italy / Adriatic Sea | 1996 | |
| Botrytella sp. | Netherlands | 1919 | |
| Bougainvillia macloviana | Germany / North Sea | 1895 | |
| Bougainvillia macloviana | Portugal / Azores | To 1989 | |
| Bougainvillia megas | Bulgaria | 1933 | |
| Bougainvillia megas | Iran / Caspian Sea | From 1956 | |
| Bougainvillia megas | Russia / Azov Sea | 1950 | |
| Bougainvillia megas | Ukraine / Black Sea | From 1960 | |
| Bougainvillia muscus | Australia / Bass strait | 1971 | |
| Bougainvillia rugosa | Sweden / North Sea | | |
| Brachidontes exustus | Ireland | 1977 | |
| Brachidontes exustus | United Kingdom (Britain) / Celtic seas | 1977 | |
| Brachidontes pharaonis | France / Western Mediterranean | 1989 | |
| Brachidontes pharaonis | Greece / Eastern Mediterranean | 1975 | |
| Brachidontes pharaonis | Israel | 1935 | |
| Brachidontes pharaonis | Italy / Central Mediterranean | 1969 | |
| Brachidontes pharaonis | Italy / Western Mediterranean | 1998 | |
| Brachynotus sexdentatus | France / Biscay Gulf | 1997 | |
| Brachynotus sexdentatus | France / English Channel | To 1963 | |
| Branchiodrilus hortensis | Belgium | To 2010 | |
| Branchiodrilus hortensis | Netherlands | To 2002 | |
| Branchiomma bairdi | Greece / Eastern Mediterranean | 2014 | |
| Branchiomma bairdi | Italy / Central Mediterranean | 2016 | |
| Branchiomma bairdi | Italy / Western Mediterranean | 2015 | |
| Branchiomma bairdi | Portugal / Madeira | 2013 | |
| Branchiomma bairdi | Spain / Canary Islands | 2012 | |
| Branchiomma boholense | Israel | 1927 | |
| Branchiomma boholense | Italy / Adriatic Sea | 2011 - 2012 | |
| Branchiomma boholense | Italy / Central Mediterranean | 2007 | |
| Branchiomma boholense | Italy / Western Mediterranean | 2004 | |
| Branchiomma bombyx | Netherlands | 1973 | |
| Branchiomma luctuosum | France / Western Mediterranean | 2022 | |
| Branchiomma luctuosum | Greece / Eastern Mediterranean | 1989 | |
| Branchiomma luctuosum | Italy / Central Mediterranean | 1998 - 1999 | |
| Branchiomma luctuosum | Italy / Western Mediterranean | 1978 - 1979 | |
| Branchiomma luctuosum | Spain / Spain | 2017 - 2018 | |
| Branchiura sowerbyi | Belgium | To 1931 | |
| Branchiura sowerbyi | Germany / Baltic Sea | To 1959 | |
| Branchiura sowerbyi | Germany / North Sea | 1961 | |
| Branchiura sowerbyi | Poland | 1976 | |
| Branchiura sowerbyi | Portugal / Azores | 2008 | |
| Brania arminii | Spain / Iberian Coastal | To 1998 | |
| Bregmaceros nectabanus | Greece / Central Mediterranean | 2016 | |
| Bregmaceros nectabanus | Greece / Eastern Mediterranean | 2014 | |
| Bregmaceros nectabanus | Israel | 2004 | |
| Bregmaceros nectabanus | Italy / Adriatic Sea | 2019 | |
| Bryopsis pennata | Israel | 1961 | |
| Bryopsis plumosa | Australia / Bass strait | 1966 | |
| Bugula avirostris | Spain / Canary Islands | To 2003 | |
| Bugula neritina | Australia / Bass strait | 1881 | |
| Bugula neritina | Belgium | 1999 | |
| Bugula neritina | France / Biscay Gulf | 2001 | |
| Bugula neritina | France / Celtic seas | 1966 | |
| Bugula neritina | France / English Channel | 2002 | |
| Bugula neritina | France / North Sea | 1973 | |
| Bugula neritina | France / Western Mediterranean | 1900 | |
| Bugula neritina | Germany / North Sea | 2010 | |
| Bugula neritina | Ireland | To 2006 | |
| Bugula neritina | Netherlands | 2007 | |
| Bugula neritina | Portugal / Azores | 2001 | |
| Bugula neritina | Portugal / Iberian Coastal | 2004 | |
| Bugula neritina | Portugal / Madeira | To 2012 | |
| Bugula neritina | Spain / Canary Islands | To 2003 | |
| Bugula neritina | Spain / Iberian Coastal | 2003 | |
| Bugula neritina | United Kingdom (Britain) / Celtic seas | To 1912 | |
| Bugula neritina | United Kingdom (Britain) / English Channel | To 1912 | |
| Bugulina calathus | Australia / Bass strait | 1978 | |
| Bugulina flabellata | Australia / Bass strait | 1982 | |
| Bugulina flabellata | New Zealand / New Zealand Shelf / North Island | To 1949 | |
| Bugulina flabellata | New Zealand / New Zealand Shelf / South Island | To 1949 | |
| Bugulina fulva | Greece / Eastern Mediterranean | 1996 | |
| Bugulina fulva | Ireland | 2012 | |
| Bugulina fulva | Portugal / Iberian Coastal | 1960 | |
| Bugulina fulva | Portugal / Madeira | 2013 | |
| Bugulina fulva | Spain / Canary Islands | To 2003 | |
| Bugulina fulva | United Kingdom (Britain) / North Sea / Orkney Islands | 2012 | |
| Bugulina simplex | Australia / Bass strait | 1982 | |
| Bugulina simplex | Belgium | 2000 | |
| Bugulina simplex | France / Biscay Gulf | 1994 | |
| Bugulina simplex | France / English Channel | 2002 | |
| Bugulina simplex | France / North Sea | 2000 | |
| Bugulina simplex | Ireland | 2011 | |
| Bugulina simplex | Netherlands | 2000 | |
| Bugulina simplex | Portugal / Azores | To 1998 | |
| Bugulina simplex | Portugal / Madeira | 2013 | |
| Bugulina simplex | United Kingdom (Britain) / Celtic seas | 1957 | |
| Bugulina simplex | United Kingdom (Britain) / North Sea / Orkney Islands | 2014 | |
| Bugulina stolonifera | Australia / Bass strait | 1880 - 1889 | |
| Bugulina stolonifera | Belgium | 1999 | |
| Bugulina stolonifera | France / Biscay Gulf | To 1994 | |
| Bugulina stolonifera | France / English Channel | 1970 | |
| Bugulina stolonifera | France / North Sea | 1970 | |
| Bugulina stolonifera | France / Western Mediterranean | 2002 | |
| Bugulina stolonifera | Germany / North Sea | To 1987 | |
| Bugulina stolonifera | Netherlands | 1993 | |
| Bugulina stolonifera | Portugal / Azores | To 1998 | |
| Bugulina stolonifera | Portugal / Iberian Coastal | 2004 | |
| Bugulina stolonifera | Portugal / Madeira | To 2010 | |
| Bugulina stolonifera | Spain / Canary Islands | To 2003 | |
| Bugulina stolonifera | United Kingdom (Britain) / Celtic seas | 1950 - 1959 | |
| Bugulina stolonifera | United Kingdom (Britain) / English Channel | 1950 - 1959 | |
| Bugulina stolonifera | United Kingdom (Britain) / North Sea | To 2005 | |
| Bulinus truncatus | Spain / Iberian Coastal | 1999 | |
| Bulla arabica | Greece / Eastern Mediterranean | 1998 | |
| Bulla arabica | Israel | 1978 | |
| Bursatella leachii | France / Western Mediterranean | 2023 | |
| Bursatella leachii | Greece / Central Mediterranean | 2003 | |
| Bursatella leachii | Greece / Eastern Mediterranean | 1975 | |
| Bursatella leachii | Italy / Adriatic Sea | 1981 | |
| Bursatella leachii | Italy / Central Mediterranean | 1968 - 1973 | |
| Bursatella leachii | Italy / Western Mediterranean | 1975 - 1976 | |
| Bythocaris cosmetops | France / Biscay Gulf | 2002 | |
| Bythocaris cosmetops | France / Celtic seas | 2002 | |
