The Family Helodermatidae consists of venomous lizards, including the Gila monster (Heloderma suspectum) and the Mexican beaded lizard (Heloderma horridum), found in arid and semi-arid regions of North and Central America. These lizards are relatively slow-moving, heavy-bodied, and covered with bead-like scales. They possess a venomous bite delivered through grooved teeth in the lower jaw, which they use primarily for subduing prey and defense. Helodermatids are opportunistic feeders, consuming small mammals, birds, eggs, and insects, and are notable for their fat-storing tails that help them survive in harsh environments. Despite their fearsome reputation, they are generally docile and spend much of their time in burrows or crevices.