Ma
- Mabuya
†Machimosaurus Von Meyer, 1837
- †Machimosaurus bathonicus Sauvage 1874
- †Machimosaurus buffetauti Young et al. 2014
- †Machimosaurus hugii Von Meyer (1837)
- †Machimosaurus mosae Sauvage and Lienard 1879
- †Machimosaurus nowackianus (von Huene. 1938)
- Machimosaurus rex Fanti et al., 2016 novootkrivena vrsta[1]
- †Machimosaurus rigauxi Sauvage 1874
Reptilia → Loricata → Neosuchia → Thalattosuchia → Teleosauridae
- Macrelaps
- Macrocalamus
Macrochelys
- Macrochelys apalachicolae Thomas, Granatosky, Bourque, Krysko, Moler, Gamble, Suarez, Leone & Roman, 2014
- Macrochelys suwanniensis Thomas, Granatosky, Bourque, Krysko, Moler, Gamble, Suarez, Leone & Roman, 2014
- Macrochelys temminckii Troost, 1835
Reptilia → Testudines → Cryptodira → Chelydridae
- Macropholidus
- Macropisthodon
- Macroprotodon
- Macrovipera
- Madagascarophis
- Madascincus
- Magliophis
- Malaclemys
- Malacochersus
- Malayemys
- Malpolon
- Manciola
- Manolepis
- Manouria
- Mantheyus
- Maracaiba
- Marinussaurus
- Marisora
- Marmorosphax
†Nadporodica Mosasauroidea Gervais 1853
- Porodica Aigialosauridae Kramberger 1892
- Porodica Mosasauridae
- Niži taksoni: Komensaurus, Tethysaurinae, Vallecillosaurus
Animalia → Chordata → Reptilia → Squamata → Sauria → Lacertilia
- Mastigodryas
- Matoatoa
- Mauremys
Me
- Mecistops
- Mediodactylus
- Medopheos
- Megatyphlops
- Meizodon
- Melanochelys
- Melanophidium
- Melanoseps
- Melanosuchus
- Menetia
- Meroles
- Mesalina
- Mesaspis
- Mesobaena
- Mesoclemmys
- Mesoscincus
Mi
- Micrablepharus
- Micrelaps
- Microgecko
- Microlophus
- Micropechis
- Micropisthodon
- Micruroides
- Micrurus
†Podred Millerosauroidea
Reptilia → Anapsida → Captorhinida
- Mimophis
- Mitophis
- Mixcoatlus
Mn
- Mniarogekko
Mo
- Mochlus
- Mokopirirakau
- Moloch
- Monopeltis
- Montaspis
- Montatheris
- Montivipera
- Morelia
- Morenia
- Morethia
- Morunasaurus
Mu
- Mussurana
My
- Myersophis
- Myriopholis
- Myron
- Myrrophis
- Myuchelys