John I think that this is heatwolei - note flattened head profile, what appears to be a lack of a pale front edge to ear opening, and the elevation at Bendora Dam too low for this species. Even upstream at Corin Dam we only find heatwolei along the river.
My first impression was it was heatwolei but it appeared to have a white leading edge to the ear opening so against better judgement, I called it tympanum. The pale edge may be just light reflection. I thought it might have drawn a comment from you and happy to agree with heatwolei and change it here.