Scale rot?

[annieandziggy]

There’s always been this really dark line on Ziggys beard but recently it’s gotten darker. I noticed it’s only at the “root” of the scales. Is this scale rot or just natural coloring?

 

[KarrieRee]

There’s always been this really dark line on Ziggys beard but recently it’s gotten darker. I noticed it’s only at the “root” of the scales. Is this scale rot or just natural coloring?

Looks like coloring