The Gila monster and the Mexican beaded lizard are dangerous and poisonous lizards.
The Gila monster (Heloderma suspectrum) of the American southwest, including Mexico, is a large lizard with dark, highly textured skin marked by pinkish mottling. It averages 35 to 45 centimeters in length and has a thick, stumpy tail. Unlikely to bite unless molested, it has a poisonous bite.
Mexican Beaded Lizard
The Mexican beaded lizard (Heloderma horridum) resembles its relative, the Gila monster. It has more uniform spots rather than bands of color (the Gila monster). It also is poisonous and has a docile nature. You find it from Mexico to Central America.
This giant lizard (Varanus komodoensis) grows to more than 3 meters in length and can be dangerous if you try to capture it. This Indonesian lizard can weigh more than 135 kilograms.