Brown spots on dogs groin/tummy

Hello, just wondering if anyone could tell me what these spots are on my dog? They’ve appeared in the last few days. They’re not scabs. He has had the dark pigmentation for a while but not the spots. Just seeing if I should be worried or not or could be sorted with medicated shampoo or something? Thanks in advance! 

Hello!   I'm afraid that I can't tell be looking over this distance, but one of the main possibilities I can think of - yeast, or "Malassezia" infection - could certainly be treated using a specific medical shampoo (it was POM - prescription only - last time I checked, so only available from your vets or your pharmacy, and in the case of the pharmacy, they would have to have someone willing to prescribe it.  Therefore we would advise seeing your vet).  Bacterial infections might also be treatable this way and do sometimes cause discolouration.  However, I can't rule out anything more sinister at this stage.  Your vet may want to trial treat for superficial infection or, if they are concerned, they may ask to biopsy.  It is definitely worth going to see them.