Boyd’s Forest Dragons Hypsilurus boydii are endemic to the rainforests of Australia’s Wet Tropics. They can reach a total length of 54 cm and may live to thirty years. They prefer the vertical surface of a tree-trunk, particularly one with a slightly larger diameter than their own girth, to hide behind upon the approach of any potential threat. Occupying a territorial distribution of one dragon per 500 square metres of forest, they protect themselves from Amethystine Pythons in another peculiar way.
They distinguish themselves from all other rainforest reptiles by maintaining a consistently colder body temperature. This is achieved by avoiding exposure to direct sunlight in an unusually precautionary thermo-regulation. By ensuring that their body temperature is always precisely the same as the temperature of the vegetation upon which they sleep, they remain thermally inconspicuous to the Amethystine Python with its formidable thermo-detection capabilities.
They do, however, leave a scent trail, but this unavoidable legacy is offset by false trails and the selection of a sleeping position that replicates that of the Spectacled Monarch as described previously. Juvenile dragons sleep at the very ends of flimsy branches on under-storey plants so that their instinctive sensitivity to vibration wakes them from sleep upon the approach of a snake. Adults rely more upon the sensitivity of the tip of their tail, which is thermally indistinguishable from the tree, but some lose portions of tail which do not regenerate with this species.