Iassus scutellaris
- Group
- True bugs
- Peak month
- July
- Records since 2000
- 50
Iberian Chiffchaff
- Group
- Birds
- Peak month
- May
- Records since 2000
- 658
Iberian geranium
- Group
- Flowering plants
- Peak month
- June
- Records since 2000
- 85
Iberina montana
- Group
- Spiders
- Peak month
- August
- Records since 2000
- 98
Iceland Gull
- Group
- Birds
- Peak month
- January
- Records since 2000
- 6,693
Iceland-purslane
- Group
- Flowering plants
- Peak month
- July
- Records since 2000
- 364
Ichneumon extensorius
- Group
- Bees, wasps and ants
- Peak month
- July
- Records since 2000
- 64
Ichneumon gracilentus
- Group
- Bees, wasps and ants
- Peak month
- February
- Records since 2000
- 52
Ichneumon ingae
- Group
- Bees, wasps and ants
- Peak month
- July
- Records since 2000
- 333
Ichneumon sarcitorius
- Group
- Bees, wasps and ants
- Peak month
- July
- Records since 2000
- 222
Ichneumon stramentor
- Group
- Bees, wasps and ants
- Peak month
- April
- Records since 2000
- 221
Ichneumon wasp
- Group
- Bees, wasps and ants
- Peak month
- August
- Records since 2000
- 71
Ichneumon xanthorius
- Group
- Bees, wasps and ants
- Peak month
- July
- Records since 2000
- 157
Icterine Warbler
- Group
- Birds
- Peak month
- May
- Records since 2000
- 1,038
Icy Rock-moss
- Group
- Mosses
- Peak month
- August
- Records since 2000
- 62
Id
- Group
- Fish
- Peak month
- October
- Records since 2000
- 144
Idiocerus herrichii
- Group
- True bugs
- Peak month
- August
- Records since 2000
- 165
Idiocerus lituratus
- Group
- True bugs
- Peak month
- August
- Records since 2000
- 168
Idiocerus stigmaticalis
- Group
- True bugs
- Peak month
- July
- Records since 2000
- 173
Idioptera linnei
- Group
- True flies
- Peak month
- May
- Records since 2000
- 113
Idioptera pulchella
- Group
- True flies
- Peak month
- May
- Records since 2000
- 321
Idotea balthica
- Group
- Crustaceans
- Peak month
- September
- Records since 2000
- 321
Idotea chelipes
- Group
- Crustaceans
- Peak month
- September
- Records since 2000
- 264
Idotea emarginata
- Group
- Crustaceans
- Peak month
- August
- Records since 2000
- 68
Idotea linearis
- Group
- Crustaceans
- Peak month
- July
- Records since 2000
- 193
Idotea neglecta
- Group
- Crustaceans
- Peak month
- July
- Records since 2000
- 151
Idotea pelagica
- Group
- Crustaceans
- Peak month
- June
- Records since 2000
- 106
Ilex altaclerensis
- Group
- Flowering plants
- Peak month
- April
- Records since 2000
- 147
Ilione albiseta
- Group
- True flies
- Peak month
- June
- Records since 2000
- 326
Ilione lineata
- Group
- True flies
- Peak month
- July
- Records since 2000
- 156
Ilisia maculata
- Group
- True flies
- Peak month
- June
- Records since 2000
- 549
Ilisia occoecata
- Group
- True flies
- Peak month
- June
- Records since 2000
- 227
Illex illecebrosus
- Group
- Molluscs
- Peak month
- November
- Records since 2000
- 341
Illosporiopsis christiansenii
- Group
- Fungi
- Peak month
- February
- Records since 2000
- 655
Ilybius aenescens
- Group
- Beetles
- Peak month
- June
- Records since 2000
- 192
Ilybius fenestratus
- Group
- Beetles
- Peak month
- July
- Records since 2000
- 207
Ilybius guttiger
- Group
- Beetles
- Peak month
- July
- Records since 2000
- 357
Ilybius montanus
- Group
- Beetles
- Peak month
- May
- Records since 2000
- 602
Ilybius quadriguttatus
- Group
- Beetles
- Peak month
- June
- Records since 2000
- 666
Ilythea spilota
- Group
- True flies
- Peak month
- June
- Records since 2000
- 113
Imbribryum muehlenbeckii
- Group
- Mosses
- Peak month
- July
- Records since 2000
- 68
Imbricate bog-moss
- Group
- Mosses
- Peak month
- July
- Records since 2000
- 112
Immaculate Grass-veneer Moth
- Group
- Butterflies and moths
- Peak month
- July
- Records since 2000
- 1,937
Immersaria athroocarpa
- Group
- Lichens
- Peak month
- August
- Records since 2000
- 133
Immundisolibacter cernigliae
- Group
- Microorganisms and protists
- Peak month
- January
- Records since 2000
- 159
Imperforate St John's-wort
- Group
- Flowering plants
- Peak month
- July
- Records since 2000
- 1,090
Imperial Scaldfish
- Group
- Fish
- Peak month
- March
- Records since 2000
- 5,486
Impunctate Mini-miner
- Group
- Bees, wasps and ants
- Peak month
- June
- Records since 2000
- 728
Imshaugia lichen
- Group
- Lichens
- Peak month
- April
- Records since 2000
- 308
Incline distichium moss
- Group
- Mosses
- Peak month
- March
- Records since 2000
- 179
Inconspicuous ladybird
- Group
- Beetles
- Peak month
- July
- Records since 2000
- 211
Incrucipulum ciliare
- Group
- Fungi
- Peak month
- September
- Records since 2000
- 75
Incurvaria masculella
- Group
- Butterflies and moths
- Peak month
- May
- Records since 2000
- 294
Incurvaria pectinea
- Group
- Butterflies and moths
- Peak month
- April
- Records since 2000
- 181
Indian Balsam
- Group
- Flowering plants
- Peak month
- August
- Records since 2000
- 62,045
Indian Peafowl
- Group
- Birds
- Peak month
- May
- Records since 2000
- 889
Indian Rhubarb
- Group
- Flowering plants
- Peak month
- May
- Records since 2000
- 801
Indian teasel
- Group
- Flowering plants
- Peak month
- April
- Records since 2000
- 142
Indigo Bunting
- Group
- Birds
- Peak month
- May
- Records since 2000
- 64
Infectious bursal disease virus
- Group
- Microorganisms and protists
- Records since 2000
- 58
- Kingdom
- Viruses
Inflated Notchwort
- Group
- Liverworts
- Peak month
- July
- Records since 2000
- 2,387
Influenza D virus
- Group
- Microorganisms and protists
- Peak month
- January
- Records since 2000
- 101
Ingrailed Clay
- Group
- Butterflies and moths
- Peak month
- June
- Records since 2000
- 3,879
Inkstain Bolete
- Group
- Fungi
- Peak month
- August
- Records since 2000
- 271
Inlaid Grass-veneer
- Group
- Butterflies and moths
- Peak month
- July
- Records since 2000
- 3,963
Inocybe assimilata
- Group
- Fungi
- Peak month
- October
- Records since 2000
- 274
Inocybe asterospora
- Group
- Fungi
- Peak month
- October
- Records since 2000
- 351
Inocybe cincinnata
- Group
- Fungi
- Peak month
- October
- Records since 2000
- 213
Inocybe corydalina
- Group
- Fungi
- Peak month
- October
- Records since 2000
- 85
Inocybe curvipes
- Group
- Fungi
- Peak month
- October
- Records since 2000
- 125
Inocybe dulcamara
- Group
- Fungi
- Peak month
- October
- Records since 2000
- 70
Inocybe flocculosa
- Group
- Fungi
- Peak month
- October
- Records since 2000
- 265
Inocybe fraudans
- Group
- Fungi
- Peak month
- October
- Records since 2000
- 124
Inocybe glabripes
- Group
- Fungi
- Peak month
- October
- Records since 2000
- 158
Inocybe godeyi
- Group
- Fungi
- Peak month
- October
- Records since 2000
- 56
Inocybe griseolilacina
- Group
- Fungi
- Peak month
- October
- Records since 2000
- 156
Inocybe hirtella
- Group
- Fungi
- Peak month
- October
- Records since 2000
- 147
Inocybe lacera
- Group
- Fungi
- Peak month
- August
- Records since 2000
- 220
Inocybe lanuginosa
- Group
- Fungi
- Peak month
- August
- Records since 2000
- 75
Inocybe margaritispora
- Group
- Fungi
- Peak month
- September
- Records since 2000
- 85
Inocybe mixtilis
- Group
- Fungi
- Peak month
- October
- Records since 2000
- 137
Inocybe napipes
- Group
- Fungi
- Peak month
- September
- Records since 2000
- 293
Inocybe nitidiuscula
- Group
- Fungi
- Peak month
- October
- Records since 2000
- 77
Inocybe obscurobadia
- Group
- Fungi
- Peak month
- September
- Records since 2000
- 65
Inocybe petiginosa
- Group
- Fungi
- Peak month
- October
- Records since 2000
- 202
Inocybe phaeodisca
- Group
- Fungi
- Peak month
- September
- Records since 2000
- 88
Inocybe phaeoleuca
- Group
- Fungi
- Peak month
- October
- Records since 2000
- 91
Inocybe praetervisa
- Group
- Fungi
- Peak month
- September
- Records since 2000
- 139
Inocybe pusio
- Group
- Fungi
- Peak month
- August
- Records since 2000
- 58
Inocybe soluta
- Group
- Fungi
- Peak month
- August
- Records since 2000
- 50
Inocybe stellatospora
- Group
- Fungi
- Peak month
- September
- Records since 2000
- 68
Inocybe whitei
- Group
- Fungi
- Peak month
- October
- Records since 2000
- 67
Inocybe xanthomelas
- Group
- Fungi
- Peak month
- September
- Records since 2000
- 56
Inoderma subabietinum
- Group
- Lichens
- Peak month
- November
- Records since 2000
- 559
Inonotus cuticularis
- Group
- Fungi
- Peak month
- September
- Records since 2000
- 59
Inonotus obliquus
- Group
- Fungi
- Peak month
- February
- Records since 2000
- 68
Inosperma adaequatum
- Group
- Fungi
- Peak month
- September
- Records since 2000
- 71
Inosperma bongardii
- Group
- Fungi
- Peak month
- October
- Records since 2000
- 85
Inosperma calamistratum
- Group
- Fungi
- Peak month
- September
- Records since 2000
- 54
Inosperma cookei
- Group
- Fungi
- Peak month
- September
- Records since 2000
- 208
Inosperma erubescens
- Group
- Fungi
- Peak month
- June
- Records since 2000
- 67
Inosperma maculatum
- Group
- Fungi
- Peak month
- September
- Records since 2000
- 207
Intermediate Hook-moss
- Group
- Mosses
- Peak month
- July
- Records since 2000
- 1,929
Intermediate Lady's-mantle
- Group
- Flowering plants
- Peak month
- May
- Records since 2000
- 456
Intermediate Polypody
- Group
- Ferns and horsetails
- Peak month
- September
- Records since 2000
- 764
Intermediate Screw-moss
- Group
- Mosses
- Peak month
- March
- Records since 2000
- 9,811
Intermediate Water-starwort
- Group
- Flowering plants
- Peak month
- August
- Records since 2000
- 638
Interrupted clubmoss
- Group
- Clubmosses
- Peak month
- June
- Records since 2000
- 123
Intestine silverskin lichen
- Group
- Fungi
- Peak month
- June
- Records since 2000
- 68
Intricate Rim-lichen
- Group
- Lichens
- Peak month
- May
- Records since 2000
- 899
Involvulus icosandriae
- Group
- Beetles
- Peak month
- May
- Records since 2000
- 151
Iodine Bolete
- Group
- Fungi
- Peak month
- August
- Records since 2000
- 115
Iodine Bonnet
- Group
- Fungi
- Peak month
- October
- Records since 2000
- 1,435
Iodophanus carneus
- Group
- Fungi
- Peak month
- September
- Records since 2000
- 86
Ione thoracica
- Group
- Crustaceans
- Peak month
- June
- Records since 2000
- 102
Ionomidotis fulvotingens
- Group
- Fungi
- Peak month
- February
- Records since 2000
- 74
Iophon hyndmani
- Group
- Sponges
- Peak month
- August
- Records since 2000
- 259
Iophon nigricans
- Group
- Sponges
- Peak month
- May
- Records since 2000
- 300
Iphimedia eblanae
- Group
- Crustaceans
- Peak month
- April
- Records since 2000
- 79
Iphimedia minuta
- Group
- Crustaceans
- Peak month
- September
- Records since 2000
- 437
Iphimedia nexa
- Group
- Crustaceans
- Peak month
- September
- Records since 2000
- 158
Iphimedia obesa
- Group
- Crustaceans
- Peak month
- August
- Records since 2000
- 244
Iphimedia perplexa
- Group
- Crustaceans
- Peak month
- September
- Records since 2000
- 229
Iphimedia spatula
- Group
- Crustaceans
- Peak month
- August
- Records since 2000
- 381
Iphinoe serrata
- Group
- Crustaceans
- Peak month
- June
- Records since 2000
- 537
Iphinoe trispinosa
- Group
- Crustaceans
- Peak month
- July
- Records since 2000
- 1,529
Iridescent Centurion
- Group
- True flies
- Peak month
- June
- Records since 2000
- 638
Iridescent pea mussel
- Group
- Molluscs
- Peak month
- September
- Records since 2000
- 67
Iridescent Worm
- Group
- Worms (annelids)
- Peak month
- August
- Records since 2000
- 593
Iris Flea Beetle
- Group
- Beetles
- Peak month
- May
- Records since 2000
- 870
Iris Sawfly
- Group
- Bees, wasps and ants
- Peak month
- June
- Records since 2000
- 425
Iris Weevil
- Group
- Beetles
- Peak month
- May
- Records since 2000
- 188
Irish daltonia
- Group
- Mosses
- Peak month
- June
- Records since 2000
- 68
Irish damselfly
- Group
- Dragonflies and damselflies
- Peak month
- June
- Records since 2000
- 115
Iron Prominent
- Group
- Butterflies and moths
- Peak month
- August
- Records since 2000
- 2,451
Irpex latemarginatus
- Group
- Fungi
- Peak month
- October
- Records since 2000
- 52
Isabelline Shrike
- Group
- Birds
- Peak month
- October
- Records since 2000
- 333
Isabelline Wheatear
- Group
- Birds
- Peak month
- October
- Records since 2000
- 510
Isaria friesii
- Group
- Fungi
- Peak month
- March
- Records since 2000
- 74
Ischiolepta pusilla
- Group
- True flies
- Peak month
- June
- Records since 2000
- 113
Ischnoderma benzoinum
- Group
- Fungi
- Peak month
- October
- Records since 2000
- 199
Ischnomera cyanea
- Group
- Beetles
- Peak month
- May
- Records since 2000
- 420
Ischnomera sanguinicollis
- Group
- Beetles
- Peak month
- May
- Records since 2000
- 106
Ischnopoda leucopus
- Group
- Beetles
- Peak month
- June
- Records since 2000
- 68
Ischnopterapion loti
- Group
- Beetles
- Peak month
- June
- Records since 2000
- 1,199
Ischnopterapion modestum
- Group
- Beetles
- Peak month
- July
- Records since 2000
- 130
Ischnosoma splendidum
- Group
- Beetles
- Peak month
- June
- Records since 2000
- 128
Ischnus agitator
- Group
- Bees, wasps and ants
- Peak month
- July
- Records since 2000
- 60
Ischnus inquisitorius
- Group
- Bees, wasps and ants
- Peak month
- April
- Records since 2000
- 134
Ischyrocerus anguipes
- Group
- Crustaceans
- Peak month
- July
- Records since 2000
- 84
Isias clavipes
- Group
- Crustaceans
- Peak month
- August
- Records since 2000
- 296
Island cetraria lichen
- Group
- Lichens
- Peak month
- August
- Records since 2000
- 311
Isochnus sequensi
- Group
- Beetles
- Peak month
- September
- Records since 2000
- 221
Isodontia mexicana
- Group
- Bees, wasps and ants
- Peak month
- July
- Records since 2000
- 87
Isomira murina
- Group
- Beetles
- Peak month
- June
- Records since 2000
- 967
Isopaches bicrenatus
- Group
- Liverworts
- Peak month
- September
- Records since 2000
- 323
Isotoma viridis
- Group
- Springtails
- Peak month
- March
- Records since 2000
- 172
Isotomurus maculatus
- Group
- Springtails
- Peak month
- April
- Records since 2000
- 53
Isotomurus palustris
- Group
- Springtails
- Peak month
- March
- Records since 2000
- 78
Isotomurus unifasciatus
- Group
- Springtails
- Peak month
- November
- Records since 2000
- 73
Isotrias rectifasciana
- Group
- Butterflies and moths
- Peak month
- June
- Records since 2000
- 84
Issatchenkia orientalis
- Group
- Fungi
- Peak month
- January
- Records since 2000
- 76
Italian Alder
- Group
- Flowering plants
- Peak month
- August
- Records since 2000
- 1,104
Italian Lords-and-Ladies
- Group
- Flowering plants
- Peak month
- April
- Records since 2000
- 2,525
Italian Rye-grass
- Group
- Flowering plants
- Peak month
- June
- Records since 2000
- 618
Iteomyia capreae
- Group
- True flies
- Peak month
- August
- Records since 2000
- 369
Iteomyia major
- Group
- True flies
- Peak month
- August
- Records since 2000
- 248
Ithytrichia lamellaris
- Group
- Caddisflies
- Peak month
- August
- Records since 2000
- 842
Itoplectis alternans
- Group
- Bees, wasps and ants
- Peak month
- July
- Records since 2000
- 101
Itoplectis maculator
- Group
- Bees, wasps and ants
- Peak month
- July
- Records since 2000
- 155
Ivory Bonnet
- Group
- Fungi
- Peak month
- November
- Records since 2000
- 1,003
Ivory Gull
- Group
- Birds
- Peak month
- December
- Records since 2000
- 129
Ivy Bee
- Group
- Bees, wasps and ants
- Peak month
- September
- Records since 2000
- 10,833
Ivy Boring Beetle
- Group
- Beetles
- Peak month
- June
- Records since 2000
- 647
Ivy Broomrape
- Group
- Flowering plants
- Peak month
- June
- Records since 2000
- 774
Ivy-leaved Crowfoot
- Group
- Flowering plants
- Peak month
- May
- Records since 2000
- 393
Ivy-leaved Duckweed
- Group
- Flowering plants
- Peak month
- August
- Records since 2000
- 1,177
Ivy-leaved Speedwell
- Group
- Flowering plants
- Peak month
- April
- Records since 2000
- 3,722
Ivy-leaved Toadflax
- Group
- Flowering plants
- Peak month
- April
- Records since 2000
- 9,640
Ixodes canisuga
- Group
- Mites, harvestmen and other arachnids
- Peak month
- January
- Records since 2000
- 154
Ixodes persulcatus
- Group
- Mites, harvestmen and other arachnids
- Peak month
- October
- Records since 2000
- 59