I introduce you to Beanus Le Weanus, a 6-7 month old male weighing about 280 grams. No prior health issues and eats good. On the car ride from Houston to Dallas (about 4 days ago) I noticed these marks on his beard. He never gets "stress marks" anymore and has moderate experience being in the car. But these also do not look like regular marks and have never been there before. Last shed was about 2-3 weeks ago. The picture makes the one on the left look slightly smaller and lighter than it really is but the right side is definitely worse. Also on and off semi-diarrhea but he did get a bath so I could attempt to lightly toothbrush scrub the area and he took a long drink of water. Just wanting some opinions before I find a good vet and take him in.
His colors look nice and bright in general, and his head is up in the photo, so I think he is happy/content. My guess is that the marks you see are either a new patch of shed, or part of the previous shed that hasn't completed yet. Sheds will sometimes happen one right behind the other during a big growth spurt, and sometimes a shed can be very patchy (even down to a single scale in some places). I don't see any cause for alarm based on that photo. I'd just wait it out. Look for beard flaring that he might be doing to help loosen up the rest of it. No intervention should be needed though.