polychrus

from The Century Dictionary.

• noun A leading genus of lizards of the family Iguanidæ., having smooth scales, a small dewlap, no dorsal crest, and the squarish head covered with numerous plates: so called from its versicoloration. P. marmoratus inhabits Central America and portions of South America.
• noun [lowercase] A member of this genus: as, the marbled polychrus.