[d-prime]

I recently posted in regards to a mite issue I was dealing with, and after 2 weeks he/she is mite free. With that being said, this unsexed probable male has been consistently grey/brown and at times shows slight hues of green. It could be that this is actually a female, but the neck has dark markings. Regardless of the gender, I do not believe any L willamsi should be constantly grey.

The gecko is active in one area of the tank (the top), and does not like to explore. Other than that it eats normally and is active. Why is this gecko not showing its true colors? Any advice is much appreciated.

[Chum]

When you say dark markings on the neck, do you then mean the troat?
all williamsi have a dark streak running from the eye down to the neck.
Male williamsi tend to have a much darker troat than females, but females can have dark markings. Males troats can vary from nearly all black to black streaks.

A subadult male will have the same coloration as a female, beeing brown/bronze/greenish.
If the gecko is more green than brown it is must likely a male that is not showing its colors.

the geckos should not be grey no, they can be much darker than usual when stressed, but never heard of grey.

Can you give us some specs on the terrarium, temperature, humidity, lighting, size and so on.