| Labyrinthomorpha | EUKARYA>CHROMALVEOLATA>HETEROKONTAE>LABYRINTHULOMORPHA |
| Leiosporocerotopsida | see Anthocerotophyta |
| Lepidosauromorpha | EUKARYA>UNIKONTA>OPISTHOKONTA>ANIMALIA>BILATERIA>DEUTEROSTOMATA>VERTEBRATA>GNATHOSTOMATA>TETRAPODA>AMNIOTA>DIAPSIDA>LEPIDOSAUROMORPHA |
| Lichens | see Fungi |
| Liliopsida | EUKARYA>ARCHAEPLASTIDA>VIRIDIPLANTAE>STREPTOBIONTA>EMBRYOPHYTA>TRACHEOPHYTA>SPERMOPHYTA>ANGIOSPERMOPHYTA>LILIOPSIDA |
| Loricifera | EUKARYA>UNIKONTA>OPISTHOKONTA>ANIMALIA>BILATERIA>PROTOSTOMATA>ECDYSOZOA>SCALIDOPHORA>LORICIFERA |
| Lycopodophyta | EUKARYA>ARCHAEPLASTIDA>VIRIDIPLANTAE>STREPTOBIONTA>EMBRYOPHYTA>TRACHEOPHYTA>LYCOPODOPHYTA |
| Lycopodopsida | see Lycopodophyta |
| Lyginopteridopsida | see Pteridospermophyta |