Chameleon Dragons Chelosania brunnea Gray, 1845 are well known amongst naturalists of northern Australia as being one of the most cryptic and least frequently observed of Australia's large, iconic lizards. Despite their broad distribution across the savanna woodlands that dominate northern Australia, very few records exist of this species and, as a consequence, nearly nothing is known about their natural history. Here, we present records of 19 Chameleon Dragons, detected during clearing activities of a small area of semi-arid woodland at Delamere Air Weapons Range, Northern Territory. Additionally, we provide notes on sexual dimorphism, antipredator behaviour and shelter site use in this species. We discuss how some of this novel information may explain why this species is so rarely detected and suggests that this cryptic agamid may be much more common in savanna woodland than currently appreciated. [ABSTRACT FROM AUTHOR]