La
- Lacertilia,
- Lacertulus,
- Laemanctus,
- Laganosuchus Sereno & Larsson, 2009 †
- Lagerpeton
- Lagerpetonidae
- Lagosuchia,
- Lagosuchidae †
- Lagosuchus talampayensis,
- Lagosuchus,
- Lamarquesaurus,
- Lamiasaurus,
- Lanthanolania,
- Laonogekko,
- Laopteryx priscus,
- Laopteryx,
- Largocephalosaurus Cheng et al., 2012 †
- Largocephalosaurus,
- Lariosauridae,
- Lariosaurus Curinoi, 1847 †
- Lazarussuchus,
Le
- Leiocephalus,
- Leiosaurinae,
- Leiosaurus,
- Lepidosauria
- Lepidosauria,
- Lepidosauriformes,
- Lepidosauromorpha
- Lepidosauromorpha,
- Leptocleididae White, 1940 †
- Leptocleidus Andrews, 1922 †
- Leptonectes McGowan, 1996 †
- Leptopterygiidae Kuhn, 1934 †
- Leptosuchomorpha,
- Leptosuchus,
- Lestophis,
- Leurospondylus Brown, 1913 †
- Lewisuchinae,
- Lewisuchus,
Li
- Lianghusuchus †
Liaodactylus Zhou et al, 2017
- Liaodactylus primus Zhou et al, 2017 [1]
Diapsida → Pterosauria → Pterodactyloidea → Ctenochasmatidae
- Liaoningopterus Wang & Zhou, 2003 †
- Liaoxipterus Dong & Lü, 2005 †
- Liaoxisaurus,
- Libonectes Carpenter, 1997 †
- Libycosuchidae †
- Libycosuchus †
- Limnosaurus †
Liopleurodon Sauvage 1873
- †Liopleurodon ferox Sauvage 1873
- †Liopleurodon pachydeirus Seeley 1869
Diapsida → Sauropterygia → Pliosauridae
- Listromycter,
- Liushusaurus,
Lo
- Lonchodectes Hooley, 1913 †
- Lonchodectidae Unwin et al., 2000 †
- Lonchognathosaurus Maisch, Matzke & Sun, 2004 †
†Podred Longipinnati Huene 1948
- †Cymbospondylidae von Huene 1948
- †Merriamosauria Motani 1999
- †Toretocnemidae Maisch and Matzke 2000
Animalia → Diapsida → Ichthyopterygia → Hueneosauria
- Longisquamidae,
- Lophocranion,
- Lophoprosopus,
- Louisamphisbaena,
Lu
- Lucianosaurus,
- Ludodactylus Frey, Martill & Buchy, 2003 †
- Lutkesaurus,
- Lutungutali,
Ly
- Lygodactylus,