The Komodo Dragon (Varanus komodoensis) is the only dragon or, in this case, psuedo-dragon accepted by the scientific community.
Description[]
They are 3 feet high and up to 10 feet long. They are grey or greyish brown and its tongue has a yellowish appearance. These monitor lizards are large and fierce and should not be approached lightly, especially since it has a bite that can easily prove fatal. Some have even eaten humans on their home islands of Komodo and Rinca. They make a hissing sound when agitated.
Komodo dragons are most active during the day. Care must be taken when searching for them, as they have occasionally been known to eat humans and to dig up corpses buried in shallow graves. It is, therefore,not wise to get too close to them. Young Komodo dragons are usually found in trees, hiding from their cannibalistic elders.