New host records are reported for Mesocestoides sp. tetrathyridia in two species of iguanid lizards (Cophosaurus texanus and Sceloporus olivaceous) from Texas. Tetrathyridia were found free within the body cavity or encapsulated in the liver of the hosts. Prevalence of infection was generally low, with intensities ranging from 90 to over 200 tetrathyridia per host. In addition, a summary of North American lizard species reported as hosts of Mesocestoides sp. tetrathyridia is presented.