Photo: Mystery spot?

[bellaaxolotl]

Hello everyone! My female axolotl, Ginger, has a black spot on her side that she’s had ever since she was little. However, I’ve noticed recently that it’s grown a bit. She’s a wild type so has a lot of pigment spots in general, I just wanted to make sure this wasn’t anything to worry about. It’s completely flat, it doesn’t protrude out like a bump at all. If anything it looks most like a big freckle. I don’t have much to compare it to size-wise, but it’s probably about the size of the tip of a Q-tip. Any ideas of what it might be? Should I be worried?

 

[Hayleyy]

I can't open the pictures but from the description it sounds like pigmentation