| Species |
Recipient region |
Date of the first record |
|
| Naineris setosa | Italy / Central Mediterranean | 2019 |  |
| Naineris setosa | Italy / Western Mediterranean | 2010 | |
| Nanostrea fluctigera | Israel | 2004 | |
| Naria turdus | Israel | 1980 | |
| Naria turdus | Italy / Central Mediterranean | 2005 | |
| Nassa situla | Israel | 2004 | |
| Nassarius concinnus | Israel | 1968 | |
| Nassarius mutabilis | Spain / Iberian Coastal | 2006 | |
| Nassarius obvelatus | Israel | 1968 | |
| Navicula finmarchica | Bulgaria | 1970 | |
| Navicula finmarchica | Romania | 1970 | |
| Navicula finmarchica | Ukraine / Black Sea | From 1970 | |
| Necora puber | Sweden / North Sea | 2007 | |
| Nemalion elminthoides | Australia / Bass strait | 1971 | |
| Nemalion vermiculare | France / Western Mediterranean | 2005 | |
| Nemipterus randalli | Greece / Eastern Mediterranean | 2018 | |
| Nemipterus randalli | Israel | 2005 | |
| Nemopsis bachei | Belgium | 1996 | |
| Nemopsis bachei | France / Biscay Gulf | 1953 | |
| Nemopsis bachei | France / Celtic seas | 1953 | |
| Nemopsis bachei | France / English Channel | To 1996 | |
| Nemopsis bachei | France / North Sea | 1996 | |
| Nemopsis bachei | Germany / North Sea | 1942 | |
| Nemopsis bachei | Netherlands | 1905 | |
| Nemopsis bachei | Norway / North Sea | To 1879 | |
| Nemopsis bachei | United Kingdom (Britain) / Celtic seas | 1851 | |
| Neocalanus gracilis | Romania | 1978 | |
| Neoceratium candelabrum | France / Celtic seas | 2005 | |
| Neodexiospira brasiliensis | France / Biscay Gulf | 2007 | |
| Neodexiospira brasiliensis | France / English Channel | To 1982 | |
| Neodexiospira brasiliensis | Germany / North Sea | 2014 | |
| Neodexiospira brasiliensis | Netherlands | 1985 | |
| Neodexiospira brasiliensis | United Kingdom (Britain) / English Channel | 1974 | |
| Neogobius fluviatilis | Netherlands | 2009 | |
| Neogobius fluviatilis | Poland | 1997 | |
| Neogobius kessleri | Germany / North Sea | To 2008 | |
| Neogobius kessleri | Netherlands | 2007 | |
| Neogobius melanostomus | Denmark / Baltic Sea | 2008 | |
| Neogobius melanostomus | Denmark / North Sea | 2016 | |
| Neogobius melanostomus | Estonia | 2002 | |
| Neogobius melanostomus | Finland | 2005 | |
| Neogobius melanostomus | Germany / Baltic Sea | 1998 | |
| Neogobius melanostomus | Germany / North Sea | To 2008 | |
| Neogobius melanostomus | Italy / Adriatic Sea | 2012 | |
| Neogobius melanostomus | Latvia | 2004 | |
| Neogobius melanostomus | Lithuania | 2002 | |
| Neogobius melanostomus | Netherlands | 2004 | |
| Neogobius melanostomus | Poland | 1990 | |
| Neogobius melanostomus | Russia / Baltic Sea / Kaliningrad area | 2000 | |
| Neogobius melanostomus | Russia / Baltic Sea / St. Petersburg area | 2012 | |
| Neogobius melanostomus | Sweden / Baltic Sea | 2008 | |
| Neogobius melanostomus | Sweden / North Sea | 2010 | |
| Neomeris annulata | Israel | 2003 | |
| Neomysis americana | Belgium | To 2012 | |
| Neomysis americana | France / Biscay Gulf | 2021 | |
| Neomysis americana | France / English Channel | 2017 | |
| Neomysis americana | Netherlands | To 2010 | |
| Neopyropia koreana | Italy / Central Mediterranean | To 2012 | |
| Neopyropia yezoensis | France / Western Mediterranean | 1975 | |
| Neopyropia yezoensis | Germany / North Sea | To 1984 | |
| Neopyropia yezoensis | Italy / Adriatic Sea | 2010 | |
| Neosiphonia flavimarina | France / Biscay Gulf | 2010 | |
| Neosiphonia flavimarina | France / Celtic seas | 2010 | |
| Neosiphonia flavimarina | France / English Channel | 2010 | |
| Neosiphonia sphaerocarpa | Portugal / Azores | 2005 - 2007 | |
| Neosiphonia sphaerocarpa | Portugal / Madeira | To 2001 | |
| Nephtys ciliata | Ukraine / Black Sea | From 1975 | |
| Neptunea arthritica | Bulgaria | 2000 | |
| Neptunea arthritica | Ukraine / Black Sea | From 2000 | |
| Nereis jacksoni | Italy / Adriatic Sea | To 2016 | |
| Nereis jacksoni | Italy / Western Mediterranean | 1985 | |
| Nereis persica | Israel | 1937 | |
| Nerita sanguinolenta | Greece / Eastern Mediterranean | 1969 | |
| Nerita sanguinolenta | Israel | 2019 | |
| Nikoides sibogae | Israel | 2012 | |
| Nippoleucon hinumensis | Estonia | 2022 | |
| Nippoleucon hinumensis | Finland | 2021 | |
| Nippoleucon hinumensis | Germany / Baltic Sea | 2019 | |
| Nippoleucon hinumensis | Germany / North Sea | 2024 | |
| Nitellopsis obtusa | Ireland | 2016 | |
| Nitidotellina lux | Israel | 1997 | |
| Nitophyllum stellato-corticatum | France / Western Mediterranean | 1988 | |
| Nitzschia sigmoidea | Ukraine / Black Sea | From 1986 | |
| Nonionella stella | Norway / North Sea | 2012 | |
| Notocochlis gualteriana | Israel | 1961 | |
| Notomastus aberans | Greece / Central Mediterranean | 2000 | |
| Notomastus aberans | Greece / Eastern Mediterranean | 1964 | |
| Notomastus aberans | Italy / Adriatic Sea | 1995 | |
| Notomastus aberans | Italy / Western Mediterranean | 1976 - 1977 | |
| Notopus dorsipes | Israel | 1962 | |
| Nototeredo norvagica | Greece / Eastern Mediterranean | 1940 | |
| Nototeredo norvagica | United Kingdom (Britain) / North Sea / Orkney Islands | To 1917 | |
| Novafabricia infratorquata | Italy / Adriatic Sea | 2000 | |
| Novafabricia infratorquata | Italy / Central Mediterranean | 2000 | |
| Novafabricia infratorquata | Italy / Western Mediterranean | To 2014 | |
| Novafabricia infratorquata | Spain / Iberian Coastal | To 2017 | |
