Geckos.

Question
Hi! Greetings from Ireland. I would like to know how do I tell a leopard gecko from an african fat tailed? I think I may have both. The male is quite large and the female is rather small, although she seems to be loosing weight. Thanks!

Henry.

Answer
Hi Henry,
The best way to tell the difference is to look at a picture of each species.
AFT are generally shorter than a leo. AFT are bulkier in body and tail.  They seem to almost have a tail that starts as wide as their body and stays that wide til nearing the end of the tail.
AFT tend to be a bit more acceptable of handling, but of course that isn't always true as each individual can be the exception to the "rule".
AFT usually have more banding, but again, that can vary due to various colors.
AFT have a lower temperature requirement than the leos which is why they should not be housed together.  Leos need the basking area of 92/94 degrees while the AFT warm temperature is in the upper 80's to 90 degrees. AFT generally have larger eyes.
I would check your temperatures and if you are housing them together, I would separate them even if you have two of the same species because the fact your female is loosing weight is a sign that she is either stressed for some reason(possibly the males "advances" or he is bullying her or she is ill in some way, possibly internal parasites.