Lophognathus gilberti — Gilbert’s Dragon
Also known as:
Ta-Ta Lizard
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 Lophognathus, Grammatophora, Physignathus, Gemmatophora, and Amphibolurus. For now, it is resting in its original genus of Lophognathus.

Lophognathus horneri was split from L. gilberti in 2018, but it looks like all the ones I've seen (so far) belong to L. gilberti. An easily visible distinction is that L. horneri has a white spot in its tympanum.

Bowali Visitor Centre, Kakadu National Park, Northern Territory, Australia—November 13, 2009
Gilbert’s Dragon (Lophognathus gilberti) Gilbert’s Dragon (Lophognathus gilberti)
These distinguished fellows were hanging out with a few yards of the Bowali Visitor Centre. They were obviously accustomed to the human traffic, willing to hold their positions as I got some photos. I had originally ID'ed this as Diporiphora albilabris sobria, a population of which has been reported from Bowali Visitor Centre. Thanks to Stephen Mahony for the corrected ID on iNaturalist.

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

Bardedjilidji, Kakadu National Park, Northern Territory, Australia—November 14, 2009
Gilbert’s Dragon (Lophognathus gilberti)
The light and dark bands across the back and off-white chin show that this one is either a female or a younger male.
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