I kept a male and female yearling pair together for about a year, but the male started picking at the female. They were too young to exhibit mating behavior, so I think it was territoriality or annoyance. They also skipped hibernation last winter while my single female hibernated. I ended up separating them.

The success stories I have heard regarding housing tegus together generally involve enclosures of 10 x 8 ft dimension. Even so, the male ends up being removed after breeding because the female defends her nest so aggressively. The female will even defend a destroyed nest after the eggs are removed.