Species Recorded | Taxon | Scientific Name | Common Name | Records | Latest |
| alder fly, lacewing or snake fly | Neuroptera | a Neuroptera species (unidentified) | 14 | 2013 |
| alder fly, lacewing or snake fly | Nineta flava | a green lacewing | 9 | 2020 |
| alder fly, lacewing or snake fly | Nineta vittata | a green lacewing | 4 | 2011 |
| alder fly, lacewing or snake fly | Nothochrysa capitata | a green lacewing | 3 | 2022 |
| algae or stonewort | Nitella flexilis agg. | Smooth Stonewort | 2 | 1999 |
| algae or stonewort | Nitella mucronata | Pointed stonewort | 2 | 1990 |
| algae or stonewort | Nitella mucronata var. gracillima | a stonewort | 6 | 1990 |
| algae or stonewort | Nitella opaca | Dark Stonewort | 2 | 1918 |
| algae or stonewort | Nitellopsis obtusa | Starry stonewort | 12 | 2015 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Nematinus fuscipennis | Darkwing Alder-cutter | 1 | 2008 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Nematus | a Nematus species (unidentified) | 2 | 2021 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Nematus lucidus | Torpedo Sawfly | 1 | 2022 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Nematus septentrionalis | Spotted Regal-sawfly | 3 | 2021 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Nemeritis macrocentra | an insect - hymenopteran | 1 | 2008 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Neodiprion sertifer | Fox-coloured Pine Combhorn | 1 | 2019 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Netelia | a Netelia species (unidentified) | 2 | 2021 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Netelia cristata | an insect - hymenopteran | 3 | 1997 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Netelia fuscicornis | an insect - hymenopteran | 4 | 2003 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Netelia inedita | an insect - hymenopteran | 1 | 2018 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Netelia latungula | an insect - hymenopteran | 1 | 1994 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Netelia nigricarpa | an insect - hymenopteran | 3 | 2008 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Netelia opacula | an insect - hymenopteran | 4 | 1998 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Netelia virgata | an insect - hymenopteran | 1 | 1998 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Neuroterus albipes | Smooth Spangle Gall | 12 | 2019 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Neuroterus albipes f. agamic | Smooth Spangle Gall Causer | 4 | 1998 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Neuroterus albipes f. sexual | Schenck's Gall Causer | 2 | 1998 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Neuroterus anthracinus | Oyster Gall | 8 | 1999 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Neuroterus anthracinus f. agamic | Oyster-gall Causer | 2 | 1996 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Neuroterus numismalis | Silk-button Spangle Gall | 20 | 2021 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Neuroterus numismalis f. agamic | Silk-button Causer | 3 | 1996 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Neuroterus quercusbaccarum | Common Spangle Gall | 64 | 2022 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Neuroterus quercusbaccarum f. agamic | Common Spangle Causer | 15 | 2011 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Neuroterus quercusbaccarum f. sexual | Currant Gall Causer | 10 | 2003 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Neuroterus tricolor | a gall wasp | 2 | 2009 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Neurotoma saltuum | Social Pear Spinner | 2 | 2017 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Nomada | a Nomada species (unidentified) | 21 | 2023 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Nomada conjungens | Fringeless Nomad Bee | 5 | 2006 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Nomada fabriciana | Fabricius' Nomad Bee | 22 | 2025 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Nomada ferruginata | Yellow-shouldered Nomad Bee | 1 | 2013 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Nomada flava | Flavous Nomad Bee | 50 | 2024 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Nomada flavoguttata | Little Nomad Bee | 39 | 2021 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Nomada flavopicta | Blunthorn Nomad Bee | 2 | 2006 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Nomada fucata | Painted Nomad Bee | 14 | 2021 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Nomada fulvicornis | 6-banded Nomad Bee | 1 | 2002 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Nomada goodeniana | Gooden's Nomad Bee | 27 | 2023 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Nomada guttulata | Short-spined Nomad Bee | 1 | 2000 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Nomada hirtipes | Long-horned Nomad Bee | 11 | 2023 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Nomada integra | Catsear Nomad Bee | 2 | 2000 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Nomada lathburiana | Lathbury's Nomad Bee | 16 | 2023 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Nomada leucophthalma | Early Nomad Bee | 2 | 2019 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Nomada marshamella | Marsham's Nomad Bee | 33 | 2021 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Nomada panzeri sensu lato | Panzer's Nomad Bee | 13 | 2020 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Nomada ruficornis | Red-horned Nomad Bee | 23 | 2024 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Nomada rufipes | Golden-rod Nomad Bee | 1 | 2000 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Nomada sheppardana | Dark Nomad Bee | 3 | 2023 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Nomada striata | Blunt-jawed Nomad Bee | 2 | 1997 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Nysson dimidiatus | Small Spurred Digger Wasp | 3 | 2001 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Nysson spinosus | Large Spurred Digger Wasp | 1 | 1999 |
| ant, bee, wasp, sawfly or ichneumon (and others) | Nysson trimaculatus | a solitary wasp | 5 | 1999 |
| bacterium | Nostoc commune | Star Jelly | 9 | 2019 |
| beetle | Nacerdes melanura | Wharf Borer | 3 | 2018 |
| beetle | Nalassus laevioctostriatus | a darkling beetle | 8 | 2012 |
| beetle | Nanophyes marmoratus | Loosestrife Weevil | 24 | 2023 |
| beetle | Nargus velox | a round fungus beetle | 69 | 2023 |
| beetle | Nargus wilkini | a round fungus beetle | 44 | 2021 |
| beetle | Nartus grapii | a water beetle | 45 | 2018 |
| beetle | Nebria | a Nebria species (unidentified) | 4 | 2023 |
| beetle | Nebria brevicollis | European Gazelle Beetle | 209 | 2023 |
| beetle | Nebria rufescens | a ground beetle | 1 | 1938 |
| beetle | Nebria salina | a ground beetle | 1 | 2007 |
| beetle | Nebrioporus elegans | a water beetle | 8 | 2013 |
| beetle | Necrobia rufipes | Copra Beetle | 1 | 1979 |
| beetle | Necrobia violacea | a chequered beetle | 3 | 2002 |
| beetle | Necrodes littoralis | Shore sexton beetle | 24 | 2023 |
| beetle | Nedyus | a Cidnorhinus species (unidentified) | 1 | 2023 |
| beetle | Nedyus quadrimaculatus | Small Nettle Weevil | 111 | 2023 |
| beetle | Neocoenorrhinus germanicus | Strawberry Rhynchites | 10 | 2023 |
| beetle | Neocrepidodera ferruginea | Wheat Flea Beetle | 16 | 2020 |
| beetle | Neocrepidodera transversa | a leaf beetle | 34 | 2023 |
| beetle | Nephus limonii/redtenbacheri agg. | a ladybird | 1 | 2009 |
| beetle | Nephus quadrimaculatus | a ladybird | 2 | 2021 |
| beetle | Neuraphes elongatulus | a small antlike beetle | 13 | 2020 |
| beetle | Nicrophorus | a Nicrophorus beetle (unidentified) | 2 | 2021 |
| beetle | Nicrophorus humator | Black Sexton Beetle | 38 | 2023 |
| beetle | Nicrophorus interruptus | a sexton beetle | 2 | 2020 |
| beetle | Nicrophorus investigator | a sexton beetle | 3 | 2020 |
| beetle | Nicrophorus vespillo | Common Burying Beetle | 22 | 2022 |
| beetle | Nicrophorus vespilloides | a sexton beetle | 16 | 2025 |
| beetle | Nicrophorus vestigator | a sexton beetle | 3 | 1982 |
| beetle | Nimbus contaminatus | a dung beetle or chafer | 2 | 2015 |
| beetle | Nimbus obliteratus | a dung beetle or chafer | 3 | 2021 |
| beetle | Niptus hololeucus | Golden Spider Beetle | 2 | 1972 |
| beetle | Nitidulidae | a Nitidulidae species (unidentified) | 1 | 2015 |
| beetle | Notaris acridulus | a weevil | 8 | 2021 |
| beetle | Notaris scirpi | a weevil | 1 | 2014 |
| beetle | Noteridae | Diving Beetle | 2 | 2013 |
| beetle | Noterus | a Noterus species (unidentified) | 4 | 2023 |
| beetle | Noterus clavicornis | Larger Noterus | 161 | 2023 |
| beetle | Notiophilus | a Notiophilus species (unidentified) | 2 | 2021 |
| beetle | Notiophilus aquaticus | a ground beetle | 6 | 2000 |
| beetle | Notiophilus biguttatus | a ground beetle | 125 | 2023 |
| beetle | Notiophilus germinyi | a ground beetle | 1 | 1993 |
| beetle | Notiophilus palustris | a ground beetle | 7 | 2023 |
| beetle | Notiophilus quadripunctatus | a ground beetle | 1 | 1999 |
| beetle | Notiophilus rufipes | a ground beetle | 18 | 2017 |
| beetle | Notiophilus substriatus | a ground beetle | 2 | 1999 |
| beetle | Notoxus monoceros | Monoceros Beetle | 5 | 2019 |
| bird | Netta rufina | Red-crested Pochard | 514 | 2022 |
| bird | Numenius | a Numenius species (unidentified) | 1 | 2017 |
| bird | Numenius arquata | Curlew | 14408 | 2025 |
| bird | Numenius phaeopus | Whimbrel | 4035 | 2024 |
| bird | Numida meleagris | Helmeted Guinea-Fowl | 5 | 2019 |
| bird | Nycticorax nycticorax | Night Heron | 3 | 2020 |
| bird | Nymphicus hollandicus | Cockatiel | 11 | 2022 |
| bug | Nabidae | a Nabidae species (unidentified) | 1 | 2013 |
| bug | Nabis | a Nabis species (unidentified) | 2 | 2023 |
| bug | Nabis (Dolichonabis) limbatus | Marsh Damselbug | 66 | 2023 |
| bug | Nabis (Nabicula) flavomarginatus | Broad Damselbug | 39 | 2024 |
| bug | Nabis (Nabis) brevis | a damsel bug | 1 | 1997 |
| bug | Nabis (Nabis) ericetorum | Heath Damselbug | 3 | 2022 |
| bug | Nabis (Nabis) ferus | Field Damsel Bug | 42 | 2025 |
| bug | Nabis (Nabis) pseudoferus | a damsel bug | 2 | 2021 |
| bug | Nabis (Nabis) rugosus | Common Damselbug | 99 | 2025 |
| bug | Nasonovia (Nasonovia) ribisnigri | Currant-Lettuce Aphid | 12 | 1975 |
| bug | Naucoridae | a Naucoridae species (unidentified) | 1 | 1993 |
| bug | Neides tipularius | a stiltbug | 2 | 2017 |
| bug | Neolygus contaminatus | a plantbug or grassbug | 4 | 2024 |
| bug | Neolygus viridis | a plantbug or grassbug | 9 | 2025 |
| bug | Neophilaenus campestris | a froghopper | 11 | 2009 |
| bug | Neophilaenus lineatus | a froghopper | 16 | 2023 |
| bug | Neotoxoptera formosana | Onion Aphid | 1 | 2018 |
| bug | Neottiglossa pusilla | a shield bug | 1 | 2006 |
| bug | Nepa | a Nepa species (unidentified) | 1 | 1988 |
| bug | Nepa cinerea | Water Scorpion | 134 | 2023 |
| bug | Nepidae | a Nepidae species (unidentified) | 2 | 1995 |
| bug | Nezara viridula | Southern Green Shieldbug | 5 | 2016 |
| bug | Notonecta | Back-Swimmer | 177 | 2023 |
| bug | Notonecta marmorea | a backswimmer | 39 | 2007 |
| bug | Notonecta (Notonecta) glauca | Common Backswimmer | 232 | 2020 |
| bug | Notonecta (Notonecta) maculata | a backswimmer | 22 | 2022 |
| bug | Notonecta (Notonecta) obliqua | a backswimmer | 5 | 2014 |
| bug | Notonecta (Notonecta) viridis | a backswimmer | 10 | 2023 |
| bug | Notostira | a Notostira species (unidentified) | 1 | 2023 |
| bug | Notostira elongata | a plantbug or grassbug | 211 | 2024 |
| bug | Notus flavipennis | a leafhopper | 1 | 2009 |
| bug | Nysius | a Nysius ground bug (unidentified) | 1 | 2019 |
| bug | Nysius huttoni | Wheat Bug | 10 | 2023 |
| bug | Nysius senecionis | a ground bug | 1 | 2021 |
| bug | Nysius thymi | a ground bug | 2 | 2009 |
| crustacean | Necora puber | Velvet Swimming Crab | 1 | 1921 |
| crustacean | Neomysis integer | an opossum shrimp | 3 | 1973 |
| crustacean | Niphargus fontanus | an amphipod | 1 | 1963 |
| crustacean | Niphargus kochianus sensu lato | a Crustacean | 1 | 1963 |
| diatom | Navicula | a Navicula species (unidentified) | 1 | 2015 |
| diatom | Navicula capitata | a diatom | 1 | 2015 |
| diatom | Navicula digitoradiata | a diatom | 1 | 2015 |
| diatom | Navicula gregaria | a diatom | 1 | 2015 |
| diatom | Navicula tripunctata | a diatom | 1 | 2015 |
| diatom | Nitzschia | a Nitzschia species (unidentified) | 1 | 2010 |
| false scorpion | Neobisiidae | a Neobisiidae species (unidentified) | 1 | 2023 |
| false scorpion | Neobisium (Neobisium) carcinoides | Common Neobisid | 5 | 2022 |
| flea | Nosopsyllus (Nosopsyllus) fasciatus | rat flea | 1 | 1954 |
| flea | Nycteridopsylla longiceps | a pipistrelle bat flea | 1 | 2016 |
| fungus | Naetrocymbe punctiformis | a fungus | 7 | 2016 |
| fungus | Naevia punctiformis | a fungus | 3 | 2010 |
| fungus | Narcissea cordispora | Ticker Inkcap | 2 | 2007 |
| fungus | Narcissea ephemeroides | Diaphanous Inkcap | 1 | 2004 |
| fungus | Narcissea patouillardii | Composting Inkcap | 1 | 2001 |
| fungus | Naucoria alnetorum | an agaric | 3 | 2003 |
| fungus | Naucoria bohemica | an agaric | 2 | 2001 |
| fungus | Naucoria escharioides | Ochre Aldercap | 20 | 2020 |
| fungus | Naucoria luteolofibrillosa | an agaric | 5 | 2008 |
| fungus | Naucoria scolecina | Cinnamon Aldercap | 2 | 1997 |
| fungus | Naucoria spadicea | a fungus | 1 | 2006 |
| fungus | Naucoria striatula | Striate Aldercap | 13 | 2008 |
| fungus | Naucoria subconspersa | Scurfy Aldercap | 8 | 2020 |
| fungus | Naucoria submelinoides | a fungus | 1 | 2020 |
| fungus | Nectria | a Nectria fungus (unidentified) | 1 | 2011 |
| fungus | Nectria cinnabarina | Coral-spot Fungus | 112 | 2023 |
| fungus | Nectriopsis rexiana | a fungus | 2 | 2008 |
| fungus | Nemania effusa | an ascomycete fungus | 5 | 2007 |
| fungus | Nemania serpens | an ascomycete fungus | 7 | 2013 |
| fungus | Neoboletus praestigiator | Scarletina Bolete | 13 | 2017 |
| fungus | Neobulgaria pura var. foliacea | an ascomycete fungus | 4 | 2013 |
| fungus | Neobulgaria pura var. pura | Beech Jellydisc | 9 | 2010 |
| fungus | Neocosmospora haematococca | an ascomycete fungus | 1 | 2005 |
| fungus | Neoerysiphe galeopsidis | Mint Mildew | 5 | 2022 |
| fungus | Neoerysiphe galii | a conidial powdery mildew | 1 | 2009 |
| fungus | Neohygrocybe nitrata | Nitrous Waxcap | 9 | 2015 |
| fungus | Neohygrocybe ovina | Blushing Waxcap | 1 | 1999 |
| fungus | Neonectria coccinea | an ascomycete fungus | 5 | 2014 |
| fungus | Neonectria ditissima | Apple and Pear Canker | 4 | 2005 |
| fungus | Neosetophoma samarorum | a fungus | 10 | 2014 |
| fungus | Niptera lychnidis | an ascomycete fungus | 1 | 1997 |
| fungus | Nitschkia collapsa | an ascomycete fungus | 2 | 2009 |
| fungus | Nitschkia confertula | an ascomycete fungus | 1 | 2010 |
| fungus | Nolanea | a Nolanea fungus (unidentified) | 1 | 1996 |
| fungus | Normandina pulchella | an ascomycete fungus | 3 | 2023 |
| hairworm | Nematomorpha | a Nematomorpha species (unidentified) | 1 | 2014 |
| harvestman | Nelima gothica | a harvestman | 9 | 2018 |
| harvestman | Nemastoma bimaculatum | a harvestman | 21 | 2023 |
| lichen | Naetrocymbe saxicola | a lichen | 1 | 2018 |
| mammal | Neomys fodiens | Water Shrew | 83 | 2025 |
| mammal | Neovison vison | American Mink | 378 | 2024 |
| mammal - bat | Nyctalus | Nyctalus Bat species | 54 | 2023 |
| mammal - bat | Nyctalus/Eptesicus agg. | a Nyctalus or a Eptesicus bat species (unidentified) | 30 | 2022 |
| mammal - bat | Nyctalus leisleri | Leisler's Bat | 414 | 2025 |
| mammal - bat | Nyctalus noctula | Noctule | 1368 | 2025 |
| millipede | Nanogona polydesmoides | Eyed Flat-backed Millipede | 9 | 2019 |
| millipede | Nemasoma varicorne | a millipede | 1 | 1998 |
| mollusc | Nesovitrea (Perpolita) hammonis | Rayed Glass Snail | 7 | 2002 |
| mollusc | Nucella lapillus | Dog Whelk | 22 | 2025 |
| mollusc | Nucula nitidosa | a mollusc | 1 | 1976 |
| moss | Neckera complanata | Flat Neckera | 65 | 2023 |
| moss | Neckera crispa | Crisped Neckera | 27 | 2023 |
| moss | Neckera pumila | Dwarf Neckera | 2 | 2018 |
| moth or butterfly - butterfly | Nymphalidae | a fritillary butterfly (unidentified) | 15 | 2018 |
| moth or butterfly - butterfly | Nymphalis antiopa | Camberwell Beauty | 19 | 2004 |
| moth or butterfly - butterfly | Nymphalis polychloros | Large Tortoiseshell | 19 | 2011 |
| moth or butterfly - macro moth | Naenia typica | Gothic | 309 | 2024 |
| moth or butterfly - macro moth | Nebula salicata subsp. latentaria | Striped Twin-spot Carpet | 2 | 1961 |
| moth or butterfly - macro moth | Noctua | a Noctua species (unidentified) | 4 | 2023 |
| moth or butterfly - macro moth | Noctua comes | Lesser Yellow Underwing | 4809 | 2024 |
| moth or butterfly - macro moth | Noctua fimbriata | Broad-bordered Yellow Underwing | 1408 | 2025 |
| moth or butterfly - macro moth | Noctua interjecta | Least Yellow Underwing | 64 | 2024 |
| moth or butterfly - macro moth | Noctua interjecta caliginosa | Least Yellow Underwing | 388 | 2024 |
| moth or butterfly - macro moth | Noctua janthe | Lesser Broad-bordered Yellow Underwing | 3375 | 2025 |
| moth or butterfly - macro moth | Noctua janthina | Langmaid's Yellow Underwing | 5 | 2020 |
| moth or butterfly - macro moth | Noctua orbona | Lunar Yellow Underwing | 12 | 2020 |
| moth or butterfly - macro moth | Noctua pronuba | Large Yellow Underwing | 10264 | 2025 |
| moth or butterfly - macro moth | Noctuidae | a Noctuidae species (unidentified) | 10 | 2024 |
| moth or butterfly - macro moth | Nola confusalis | Least Black Arches | 334 | 2024 |
| moth or butterfly - macro moth | Nola cucullatella | Short-cloaked Moth | 281 | 2024 |
| moth or butterfly - macro moth | Nonagria typhae | Bulrush Wainscot | 100 | 2024 |
| moth or butterfly - macro moth | Notodonta dromedarius | Iron Prominent | 660 | 2025 |
| moth or butterfly - macro moth | Notodonta ziczac | Pebble Prominent | 627 | 2024 |
| moth or butterfly - macro moth | Nudaria mundana | Muslin Footman | 272 | 2024 |
| moth or butterfly - macro moth | Nycteola degenerana | Swallow Nycteoline | 1 | 2022 |
| moth or butterfly - macro moth | Nycteola revayana | Oak Nycteoline | 192 | 2023 |
| moth or butterfly - macro moth | Nycterosea obstipata | Gem | 75 | 2023 |
| moth or butterfly - micro moth | Narycia | a Narycia species (unidentified) | 2 | 2015 |
| moth or butterfly - micro moth | Narycia duplicella | White-speckled Smoke | 6 | 2019 |
| moth or butterfly - micro moth | Nemapogon | a Nemapogon species (unidentified) | 1 | 2020 |
| moth or butterfly - micro moth | Nemapogon clematella | Black-barred Fungus Moth | 20 | 2023 |
| moth or butterfly - micro moth | Nemapogon cloacella | Cork Moth | 78 | 2024 |
| moth or butterfly - micro moth | Nemapogon granella | Corn Moth | 1 | 2000 |
| moth or butterfly - micro moth | Nemapogon koenigi | White-speckled Fungus Moth | 5 | 2019 |
| moth or butterfly - micro moth | Nemapogon ruricolella | Rufous Fungus Moth | 2 | 2020 |
| moth or butterfly - micro moth | Nematopogon | a Nematopogon species (unidentified) | 5 | 2023 |
| moth or butterfly - micro moth | Nematopogon metaxella | Dark-dotted Longhorn | 131 | 2024 |
| moth or butterfly - micro moth | Nematopogon schwarziellus | Sandy Longhorn | 56 | 2023 |
| moth or butterfly - micro moth | Nematopogon swammerdamella | Large Longhorn | 92 | 2024 |
| moth or butterfly - micro moth | Nemophora | a Nemophora species (unidentified) | 3 | 2015 |
| moth or butterfly - micro moth | Nemophora cupriacella | Copper-tip Longhorn | 15 | 2019 |
| moth or butterfly - micro moth | Nemophora degeerella | Yellow-banded Longhorn | 90 | 2023 |
| moth or butterfly - micro moth | Nemophora metallica | Brassy Long-horn | 44 | 2023 |
| moth or butterfly - micro moth | Nemophora minimella | Small Scabious Longhorn | 8 | 2019 |
| moth or butterfly - micro moth | Neocochylis dubitana | White-faced Straw | 24 | 2023 |
| moth or butterfly - micro moth | Neocochylis hybridella | White-fronted Straw | 78 | 2023 |
| moth or butterfly - micro moth | Neocochylis molliculana | Tawny-fronted Straw | 103 | 2024 |
| moth or butterfly - micro moth | Neofaculta ericetella | Heather Groundling | 2 | 2004 |
| moth or butterfly - micro moth | Neosphaleroptera nubilana | Deep Brown Shade | 7 | 2019 |
| moth or butterfly - micro moth | Neotelphusa sequax | Rock-rose Moth | 15 | 2019 |
| moth or butterfly - micro moth | Nephopterix angustella | Spindle Knot-horn | 165 | 2024 |
| moth or butterfly - micro moth | Niditinea fuscella | Brown-dotted Clothes Moth | 8 | 2010 |
| moth or butterfly - micro moth | Nomophila noctuella | Rush Veneer | 1386 | 2025 |
| moth or butterfly - micro moth | Noorda moringae | Drumstick Pearl | 1 | 2013 |
| moth or butterfly - micro moth | Notocelia | a Notocelia tortrix moth (unidentified) | 3 | 2020 |
| moth or butterfly - micro moth | Notocelia cynosbatella | Black Cloak | 352 | 2024 |
| moth or butterfly - micro moth | Notocelia roborana | Large Rose Shoot Moth | 35 | 2021 |
| moth or butterfly - micro moth | Notocelia rosaecolana | Rose Shoot Moth | 118 | 2024 |
| moth or butterfly - micro moth | Notocelia trimaculana | Hawthorn Shoot Moth | 129 | 2024 |
| moth or butterfly - micro moth | Notocelia uddmanniana | Bramble Shoot Moth | 418 | 2024 |
| moth or butterfly - micro moth | Nymphula nitidulata | Beautiful China-mark | 71 | 2024 |
| plant | Narcissus | Daffodil | 56 | 2023 |
| plant | Narcissus agg. | a daffodil | 318 | 2018 |
| plant | Narcissus hispanicus | Spanish Daffodil | 3 | 2013 |
| plant | Narcissus minor | Lesser daffodil | 1 | 2018 |
| plant | Narcissus obvallaris | Tenby Daffodil | 1 | 1986 |
| plant | Narcissus poeticus | Pheasant's-eye Daffodil | 6 | 2018 |
| plant | Narcissus poeticus x tazetta = N. x medioluteus | Primrose-peerless | 2 | 1986 |
| plant | Narcissus pseudonarcissus | Daffodil | 44 | 2023 |
| plant | Narcissus pseudonarcissus subsp. pseudonarcissus | Wild Daffodil | 155 | 2023 |
| plant | Nardus stricta | Mat-grass | 16 | 2008 |
| plant | Nassella tenuissima | Argentine Needle-grass | 10 | 2020 |
| plant | Nasturtium microphyllum | Narrow-fruited Water-cress | 27 | 2016 |
| plant | Nasturtium officinale | Water-cress | 323 | 2021 |
| plant | Nasturtium officinale agg. | Water-cress Spp | 674 | 2025 |
| plant | Nasturtium officinale x microphyllum = N. x sterile | Hybrid Water-cress | 1 | 1954 |
| plant | Nemesia strumosa | Cape-jewels | 1 | 2003 |
| plant | Nemophila menziesii | Baby's-blue-eyes | 1 | 2019 |
| plant | Neolitsea sericea | a neolitsea tree | 1 | 2015 |
| plant | Neotinea ustulata | Burnt Orchid | 1 | 1913 |
| plant | Neottia nidus-avis | Bird's-nest Orchid | 67 | 2023 |
| plant | Neottia ovata | Common Twayblade | 413 | 2024 |
| plant | Nepeta | a Nepeta species (unidentified) | 1 | 2013 |
| plant | Nepeta cataria | Cat-mint | 9 | 2013 |
| plant | Nepeta nepetella x racemosa = N. x faassenii | Garden Cat-mint | 14 | 2018 |
| plant | Nerine | a Nerine species (unidentified) | 1 | 2010 |
| plant | Neslia paniculata | Ball Mustard | 3 | 1957 |
| plant | Nicandra physalodes | Apple of Peru | 20 | 2020 |
| plant | Nicotiana alata | Sweet Tobacco | 6 | 2020 |
| plant | Nicotiana alata x forgetiana = N. x sanderae | Hybrid Tobacco | 3 | 2017 |
| plant | Nicotiana forgetiana | Red Tobacco | 1 | 1996 |
| plant | Nicotiana rustica | Wild Tobacco | 1 | 1988 |
| plant | Nigella | a Nigella species (unidentified) | 1 | 1984 |
| plant | Nigella arvensis | a Plant | 1 | 2017 |
| plant | Nigella damascena | Love-in-a-mist | 139 | 2025 |
| plant | Noccaea caerulescens | Alpine Penny-cress | 8 | 2007 |
| plant | Nonea lutea | Nonea lutea | 1 | 2023 |
| plant | Nothofagus alpina | Rauli | 2 | 2000 |
| plant | Nothofagus dombeyi | Dombey's Beech | 2 | 2000 |
| plant | Nothofagus obliqua | Roble | 3 | 2022 |
| plant | Notobasis syriaca | Syrian Thistle | 1 | 1937 |
| plant | Nuphar lutea | Yellow Water-lily | 184 | 2023 |
| plant | Nymphaea | a Nymphaea water-lily species (unidentified) | 4 | 2023 |
| plant | Nymphaea alba | White Water-lily | 62 | 2023 |
| plant | Nymphaea alba subsp. alba | a white water-lily | 32 | 1997 |
| plant | Nymphaeaceae | a water-lily (unidentified) | 16 | 2021 |
| plant | Nymphaea x marliacea | Water-Lily | 4 | 2014 |
| plant | Nymphoides peltata | Fringed Water-lily | 43 | 2023 |
| reptile | Natrix helvetica | Grass Snake | 765 | 2025 |
| roundworm (nematoda) | Nematoda | Nematode | 4 | 2013 |
| sea-fan, sea anemone or jellyfish | Nematostella vectensis | Starlet Sea Anemone | 1 | 1998 |
| sea spider (pycnogonida) | Nymphon gracile | Gangly Lancer | 1 | 1936 |
| spider | Neon reticulatus | a jumping spider | 3 | 2008 |
| spider | Neottiura bimaculata | a comb-footed spider | 25 | 2018 |
| spider | Neriene clathrata | a money spider | 19 | 2025 |
| spider | Neriene montana | a money spider | 7 | 2016 |
| spider | Neriene peltata | a money spider | 17 | 2019 |
| spider | Neriene radiata | a money spider | 1 | 2023 |
| spider | Nesticus cellulanus | Comb-footed Cellar Spider | 7 | 2013 |
| spider | Nigma | a Nigma species (unidentified) | 1 | 2014 |
| spider | Nigma puella | a mesh webbed spider | 7 | 2023 |
| spider | Nuctenea umbratica | Toad Spider | 22 | 2023 |
| stonefly | Nemoura cambrica | a stonefly | 1 | 2000 |
| stonefly | Nemoura cinerea | a stonefly | 1 | 1999 |
| stonefly | Nemouridae | a Nemouridae stonefly (unidentified) | 2 | 2011 |
| stonefly | Nemurella pictetii | a stonefly | 3 | 2013 |
| tick or mite (acarine) | Neotrombicula autumnalis | Harvest Mite | 2 | 1938 |
| tick or mite (acarine) | Neumania | a Neumania species (unidentified) | 1 | 1991 |
| true fly - | Nanna fasciata | a dung fly | 2 | 2004 |
| true fly - | Nanna inermis | a dung fly | 1 | 2004 |
| true fly - | Nanna tibiella | a dung fly | 1 | 2013 |
| true fly - | Nannomyza basalis | a fly | 6 | 2020 |
| true fly - | Napomyza hirticornis | a leaf-mining fly | 3 | 2004 |
| true fly - | Nematocera | Gnat | 2 | 2023 |
| true fly - | Nemopoda nitidula | a lesser dung fly | 10 | 2022 |
| true fly - | Nemorilla floralis | a parasitic fly | 1 | 2004 |
| true fly - | Nemorimyza posticata | a leaf-mining fly | 1 | 2003 |
| true fly - | Neomyia cornicina | a muscid fly | 9 | 2023 |
| true fly - | Neomyia viridescens | a muscid fly | 5 | 2023 |
| true fly - | Nephrotoma | a Nephrotoma species (unidentified) | 12 | 2023 |
| true fly - | Norellia spinipes | a dung fly | 2 | 2020 |
| true fly - | Norellisoma flavicorne | a dung fly | 1 | 2004 |
| true fly - | Norellisoma spinimanum | a dung fly | 3 | 2023 |
| true fly - | Notiphila | a Notiphila species (unidentified) | 1 | 1990 |
| true fly - | Notiphila cinerea | a shore fly | 10 | 2013 |
| true fly - | Notiphila maculata | a shore fly | 1 | 2001 |
| true fly - | Notiphila nigricornis | a shore fly | 4 | 2023 |
| true fly - | Notiphila riparia | a shore fly | 26 | 2013 |
| true fly - | Nowickia ferox | a parasitic fly | 2 | 2023 |
| true fly - | Nyctia halterata | a flesh fly | 14 | 2023 |
| true fly - cranefly | Neolimonia dumetorum | a cranefly | 8 | 2021 |
| true fly - cranefly | Nephrotoma appendiculata | Spotted Cranefly | 47 | 2024 |
| true fly - cranefly | Nephrotoma cornicina | a cranefly | 1 | 2013 |
| true fly - cranefly | Nephrotoma flavescens | Tiger Cranefly | 18 | 2023 |
| true fly - cranefly | Nephrotoma flavipalpis | a cranefly | 23 | 2024 |
| true fly - cranefly | Nephrotoma quadrifaria | a cranefly | 32 | 2023 |
| true fly - cranefly | Nigrotipula nigra | a cranefly | 6 | 2022 |
| true fly - (diptera) | Neohaplegis glabra | an insect - true fly (Diptera) | 11 | 2013 |
| true fly - (diptera) | Notiphila graecula | an insect - true fly (Diptera) | 9 | 2009 |
| true fly - (diptera) | Notiphila venusta | an insect - true fly (Diptera) | 4 | 2022 |
| true fly - hoverfly | Neoascia | a Neoascia hoverfly (unidentified) | 1 | 2023 |
| true fly - hoverfly | Neoascia geniculata | a hoverfly | 1 | 1999 |
| true fly - hoverfly | Neoascia interrupta | a hoverfly | 1 | 1999 |
| true fly - hoverfly | Neoascia meticulosa | a hoverfly | 7 | 2017 |
| true fly - hoverfly | Neoascia podagrica | a hoverfly | 50 | 2022 |
| true fly - hoverfly | Neoascia tenur | a hoverfly | 47 | 2023 |
| true fly - midge, gnat or mosquito | Neoplatyura modesta | a fungus gnat | 1 | 2000 |
| true fly - midge, gnat or mosquito | Neoplatyura nigricauda | a fungus gnat | 1 | 2001 |
| true fly - picture-winged, conopid or stilt-legged fly | Neria cibaria | a stilt fly | 3 | 2000 |
| true fly - picture-winged, conopid or stilt-legged fly | Noeeta pupillata | a gall fly | 4 | 2022 |
| true fly - robber, empid or dolichopid fly | Neoitamus cyanurus | Common Awl Robberfly | 2 | 2015 |
| true fly - robber, empid or dolichopid fly | Neurigona pallida | a dolichopodid fly | 1 | 2020 |
| true fly - robber, empid or dolichopid fly | Neurigona quadrifasciata | a dolichopodid fly | 5 | 2022 |
| true fly - robber, empid or dolichopid fly | Neurigona suturalis | a dolichopodid fly | 3 | 2001 |
| true fly - soldier or snipe fly | Nemotelus nigrinus | All-black Snout | 8 | 2021 |
| true fly - soldier or snipe fly | Nemotelus notatus | Flecked Snout | 12 | 2016 |
| true fly - soldier or snipe fly | Nemotelus pantherinus | Fen Snout | 8 | 2023 |
| true fly - soldier or snipe fly | Nemotelus uliginosus | Barred Snout | 5 | 2016 |
| true fly - soldier or snipe fly | Neopachygaster meromelas | Silver-strips Black | 3 | 2000 |
| worm | Neoamphitrite figulus | an annelid | 6 | 1973 |
| worm | Nephtys cirrosa | White Catworm | 1 | 1973 |
| worm | Nephtys hombergii | an annelid | 4 | 1976 |
| worm | Nereis pelagica | an annelid | 4 | 1995 |
| worm | Notophyllum | a Notophyllum species (unidentified) | 1 | 2004 |