Ctenosaura acanthura, is a species of iguanid lizard found in eastern Mexico and extreme western Guatemala. The standardized English name is the Mexican spiny-tailed iguana. Confusingly however, an earlier edition of standardized names for Mexican herpetofauna called Ctenosaura acanthura the northeastern spinytailed iguana and applied the name Mexican spinytailed iguana to Ctenosaura pectinata, which was called the western spiny-tailed iguana in the second edition. It has also been referred to as the Veracruz spiny-tailed iguana and Gulf Coast spiny-tailed iguana. It is an egg laying species that is mostly herbivorous and a moderately large lizard commonly growing over one meter in total length.

The Iguanidae is a family of lizards composed of the iguanas, chuckwallas, and their prehistoric relatives, including the widespread green iguana.