Splotches on dogs skin

Hello all! my 1.5 yr old mix has recently developed some red splotches in three isolated spots under his front leg and a rear leg. see picture of the purpleish,dry, scab textured spot. I plan to take him in to get looked at. He is not really scratching these areas. He played hard at a dog bar recently and I used a new conditioner by top paw right after that play day. He is on oral flea and tick meds what does it look like?

Hello - there is a catch-all word for darkening of patches of skin:  hyperpigmentation.  However, this is a word for a symptom, or sign, and not a diagnosis.  It can be caused by various things, including melanoma (a type of cancer), which typically occurs in middle-aged dogs.  However, there may be endocrine (hormonal) reasons, or skin disease e.g. allergy, with yeast having infected the surface.  The first step is definitely for your vet to examine it properly.  A lot of vets will formulate a possibilities ('differentials') list and start ruling possibilities out from there.