Once an ubiquitious feature of gardens and the city's green spaces, the green crested lizard (Bronchocela cristatella) is now restricted to lusher parks such as Kent Ridge (manicured Bishan Park is unlikely to harbour any) and forest reserves, where this native reptile is still said to be common. In more open and urbanised areas, this green igamid has been displaced by the changaeble lizard (Calotes versicolor), an invader from the north that appeared in the 1980s. Both species are often mistaken for chameleons, a family that doesn't occur in Southeast Asia and is much more sloth-like in motion. Members of the order Squamata suffer from poor public relations in Singapore, from outright hostility to a curious inability to distinguish native monitor lizards from neotropical iguanas, which superficially resemble agamids more than varanids.
It was only recently that I caught sight of green crested lizards in the reserves, after years of failed sightings. And each time, they displayed their propensity for leaping, hurtling their lithe bodies with abandon onto the shrubbery in an almighty effort to escape my duck. Their aerial launches involve a stretch of splayed limbs and an expanded rib cage that serve to increase their body surface area and prolong their jump – features that are thought to be similar to the basal creatures that gave rise to their cousins, the Draco flying lizards. Gliding is a feature that has appeared more than once in deep time, and strangely, has been adopted by geckos, agamids and snakes (see this site for incredible videos of paradise tree snakes swimming and even changing trajectory through the air) only in Asia. Though promising, Bronchochela in Singapore has a much shorter lease to develop better flight capabilities before invasive cousins and the shrinking canopies of forests-turned-fragments combine to offer this emerald emissary of endangered environments a final leap into oblivion.
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