fossiles
| Nom | Type | Notoriété | Popularité |
|---|---|---|---|
| Inostranceviinae | Taxon | 3 | 0.0 |
| Ischigualastia | Taxon | 15 | 0.0 |
| Isodectes | Taxon | 5 | 1.3 |
| Jakubsonia | Taxon | 5 | 0.4 |
| Jammerbergia | Taxon | 5 | 0.4 |
| Jamoytius Kerwoodi | Taxon | 10 | 0.7 |
| Jarilinus | Taxon | 5 | 0.0 |
| Jinogondolella | Taxon | 2 | 0.0 |
| Jiufengia | Taxon | 3 | 0.0 |
| Jonkeria | Taxon | 13 | 0.0 |
| Julognathus | Taxon | 4 | 0.0 |
| Kadanuumuu | Concept | 12 | 1.1 |
| Kamacops | Taxon | 8 | 0.2 |
| Kamagorgon | Taxon | 8 | 0.0 |
| Kannemeyeria | Taxon | 19 | 0.8 |
| Kannemeyeriidae | Taxon | 10 | 0.9 |
| Kannemeyeriiformes | Taxon | 6 | 0.1 |
| Karenites | Taxon | 6 | 0.0 |
| Karenites | Taxon | 4 | 0.0 |
| Karpinskiosauridae | Taxon | 2 | 0.0 |
| Karpinskiosaurinae | Taxon | 1 | 0.0 |
| Karpinskiosaurus | Taxon | 8 | 0.0 |
| Kayentatherium | Taxon | 9 | 0.0 |
| Keraterpeton | Taxon | 9 | 0.1 |
| Keratobrachyops | Taxon | 5 | 0.0 |
| Kerygmachela | Taxon | 14 | 0.4 |
| Kimberella | Taxon | 23 | 1.9 |
| Kockelella | Taxon | 2 | 0.0 |
| Kockelellidae | Taxon | 2 | 0.0 |
| Konzhukovia | Taxon | 10 | 0.2 |
| Koolasuchus | Taxon | 23 | 2.8 |
| Kotelcephalon | Taxon | 1 | 0.0 |
| Krusatodon | Taxon | 4 | 0.0 |
| Kryostega | Taxon | 5 | 0.0 |
| Kwatisuchus | Taxon | 3 | 0.0 |
| Laccosaurus | Taxon | 3 | 0.1 |
| Laidleria | Taxon | 8 | 0.2 |
| Lalieudorhynchus | Taxon | 7 | 0.0 |
| Lampetra | Taxon | 22 | 1.7 |
| Lampetra Aepyptera | Taxon | 12 | 0.3 |
| Lamproie Marine | Taxon | 47 | 53.5 |
| Lamproie de Planer | Taxon | 42 | 6.7 |
| Lamproie de Rivière | Taxon | 39 | 14.0 |
| Lamproie du Nord | Taxon | 12 | 2.6 |
| Lamproie du Pacifique | Taxon | 9 | 1.4 |
| Lanarkia | Taxon | 6 | 0.0 |
| Lanarkiidae | Taxon | 2 | 0.0 |
| Laosuchus | Taxon | 5 | 0.7 |
| Lapillopsidae | Taxon | 8 | 0.1 |
| Lapillopsis | Taxon | 6 | 0.3 |