Uneven pupil contraction? (Agamura persica)

[fenrisswolf]

I was home sick with the flu for the last couple of days, and in between dozing off from the medications and lazing about the house feeling miserable, I took a look at my geckos during the day.

I happened to notice that my female spider gecko does not close both pupils to the same degree during the day. (The right side seems to remain open a bit more, and both eyes look normal at night.) She seems to react normally otherwise, she feeds well, and I can't quite tell if there is any difference in response time to visual stimulus from either side.

Any ideas on anything I could be looking out for? As long as she is feeding normally, not loosing weight, and reacting to things around her, I'm not too worried about her ability to get by, but any abnormality is always worth noting...
Both eyes seem clear and there is no obvious signs of past head trauma (as far as I could tell, but I was not really at my best, these last couple of days.)

I'll post some pictures as soon as my internet connection at home is working again...

 

[René]

I think I know what you mean, and I've seen it with my Agamura too on a regular base.
The explanation is that the light source is hanging on one side of the gecko so there's more light shining in that eye then in the eye on the other side.
So she has to make the pupil on the side of the light source narrower to prevent herself from being blinded.
I added some pics of my Agamura where you can see the difference in pupil width.

René.

 

[fenrisswolf]

That's exactly what she looks like!

I was unaware of independent pupil contraction being a possibly normal reaction, which is why I was a bit worried. As far as I know, only chameleons (and some fish) have independent eye control as a normal part of their everyday life. (Neurophysiology? I'm not quite sure of the proper term.)

Generally speaking, when that happens with other vertebrates, it's either an indicator of head trauma, or some problem with the eyes and associated tissues.

 

[René]

Generally speaking, when that happens with other vertebrates, it's either an indicator of head trauma, or some problem with the eyes and associated tissues.

Yep, that's right. But when there's head trauma, there's no pupil contraction or dilation at all or it's heavily reduced.

René.