Gargoyles can and do regenerate tails. Usually it is quite sparse and small in the ones that I have seen. Yours little one's looks especially well formed, I have to say, save for that tell tale thin tip that regen gargs get I wouldn't have necessarily jumped to "lost tail" when seeing it.

But yes, to confirm your question, cresties do not regenerate their tails, but for some reason gargoyles do regenerate.

Cute to boot!
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0.1 Albino Leo Gecko
0.1 Crested Gecko
1.0 Dear Boyfriend
Departed: Harvey and Spock