Think BCI vs BCI. Chacoans(drop the giant because larger size isn't consistent) are more or less a sales ploy these days. I do believe they started out as a specific locality import with recognizable, consistent differences in comparison to the typical farmed merianae imports. Considering the length of time they've been in the states now coupled with the careless, haphazard pairing choices folk tend to make with tegus - the chacoan title doesn't really carry much weight with me anymore.