Mauritius ornate day gecko 
Maximilian's Blue-tailed Microteiid 
Meadow Lizard 
Mediterranean House Gecko 
Mediterranean thin-toed gecko 
Melanophidium punctatum 
Meroles cuneirostris 
Merrem's Madagascar Swift 
Mertens’ Water Monitor 
Mexican Black Kingsnake 
Mexican Garter Snake 
Mexican mole lizard 
Mexican parrot snake 
Middle American Indigo Snake 
Midget Faded Rattlesnake 
Midland Watersnake 
Mindanao scaly-toed gecko 
Miri Bent-toed Gecko 
Mocquard's Eyebrow Lizard 
Modest Day Gecko 
Mohave Rattlesnake 
Mojave Desert Sidewinder 
Mojave fringe-toed lizard 
Mole skink