When we jump into leachianus geckos, we saw some leachianus geckos marked as GT. I know it's silly but we thought GT stands for something fancy like automobile term like Grand Tourer. However that is not true.
GT means in Leachianus Gecko is grand terra which means mainland of New Caledonia. That being said, leachianus gecko GT is from mainland New Caledonia region. New Caledonia is small island where surrounded by many little tiny islands.
In general, leachianus gecko GTs get bigger than Island ones. Some GT localities has longer tails than others and also longer and pointier head shape as well.
More details about GT?
Please check following link!