Slight bump on it's back near the tail
The frilled-neck lizard (Chlamydosaurus kingii), also known as the frilled lizard or frilled dragon, is a type of lizard that is found mainly in northern Australia and southern New Guinea.
This species is the only member of the genus Chlamydosaurus. Its name comes from the large frill around its neck, which usually stays folded against the lizard's body.
It is largely arboreal, spending the majority of the time in the trees. The lizard's diet consists mainly of insects and small vertebrates. The frill-necked lizard is a relatively large lizard, averaging 85 cm in length.