My name is ***** ***** I have been a Vet tech for 35+ years and have worked with Reptiles for over 40 years.
Personally I have never see dark spots on a chameleon tongue. The only issue we normally see with the mouth is stomatitis and that is also known as mouth roth and would be indicated by yellowish and dark spots on the gum line causing the inability to eat. This does not seem to be the issue.
Since Gambino is new and you have noticed this issue I suggest a Herp Vet well Chameleon check to be sure there are no issues going on.
Chameleons are very fragile and always wise to have a new one checked for any parasites and other medical issues.
I can lcoate a Herp Vet for you with a State.
I do want to dvise it is good to have a timed auto mister since Chameleons do dehydrate easily. and sometimes misting and a Dripper is not enough. I also advise the UVB light be a Reptisun 10.0 and a good calcium supplement be used 5 days as week and 2 days a Reptile vitamin. You can also add some bits of leafy greens to the diet beside the crickets and other prey. Acceptable pray are silk worms, Phoenix worms and dubia roaches.
Please it reply to discuss this information.
Please be sure you have a 10.0 UVB. Most pet shops try to sell a 5.0 which is not strong enough.
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Overall with his eating and activity level I do not think anything is wrong, but best to have him checked out to be sure.
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We have 5.0 UVB lights are not supplying adequate UVB and the Chameleons aquiring MBD because of the lack of UVB. Some of this problem may be due to the screen filtering out some of the UVB rays.
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