>>48169479GF are very inconsistent with their measuring. Some Pokemon aren't even measured from their heads. That said, the difference is Latios is accentually its length. As its 'feet' are the tufts at the back there. While Salamence is the distance its head is from the ground, due to it being a quadruped. So in order to get its true size, you have to almost double that to get its head to butt length, and then double that to get its nose to tail length. Which makes it about 4 fucking meters. That's twice the size of Latios. So yes, it is bigger.