Gowidon temporalis Northern Water Dragon
Some other names for this species:
Swamplands Lashtail
This species has bounced back and forth between several genera as further studies continue to clarify the relationships among Australian agamid lizards. It has been at various times classified as Grammatophora, Lophognathus, Physignathus, Gemmatophora, and Amphibolurus. Now it has been placed in the newly-constructed genus Gowidon.
Darwin, Northern Territory, AustraliaNovember 10, 2009
Northern Water Dragon (Gowidon temporalis)
Adult males of both Gowidon temporalis and Lophognathus gilberti appear to have been stroked with a white paint brush that started wet at the snout and dried up partway down the body.
Holmes Jungle Nature Preserve, Darwin, Northern Territory, AustraliaNovember 10, 2009
Northern Water Dragon (Gowidon temporalis)
Big lizards that look like this are common around Darwin and the rest of Australia's Top End. However, there are two closely related species that look like this, Gowidon temporalis and Lophognathus gilberti. The only surefire way to tell them apart without testing their DNA is to carefully examine the scales on their backs. On one species, the scales align in such a way as to form lines that are parallel to the spine. On the other species, the scales align in such a way as to form lines that run diagonally away from the spine. I spent a lot of time staring at my computer screen with various photos at maximum magnification in order to choose which lizards I should identify as which species.

I’ve written up an account of this three-week trip to Australia here.

Fogg Dam Conservation Reserve, Northern Territory, AustraliaNovember 11, 2009
Northern Water Dragon (Gowidon temporalis) Northern Water Dragon (Gowidon temporalis)
Sleeping on a sapling, this dragon is showing off its ridiculously long tail.
Fogg Dam Conservation Reserve, Northern Territory, AustraliaNovember 12, 2009
Northern Water Dragon (Gowidon temporalis) Northern Water Dragon (Gowidon temporalis) Northern Water Dragon (Gowidon temporalis)
After a midafternoon rainstorm, the dragons were out in force along the Fogg Dam wall. Females and juvenile males typically show some bands across the body, and less of a white paint stripe.
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