the most obvious characteristic of the skin is the colour and the texture.
That's debatable, really. Probably the most obvious characteristic of a hobbit-hole is their rounded green doors, since they can be seen even from the road.
No, it's not...
narrative; tells a story
Feathers - the only outwardly obvious characteristic unique to birds.
Skin colour, hair colour, eye colour, height - any of these will answer your question.
The audience can participate.
valance, although there is lot of variation here as well.
The most significant distinguishing characteristic of granuloma inguinale is the skin ulcer, which is larger than in most other diseases, painless, irregular in shape, and likely to bleed when touched.
Less pigmentation in your skin (substance in your tissues that produces a characteristic color).
there stingers and flappy skin
well stepping on then is the most obvious solution BUT otherwise applying salt to their skin
Hepatitis affects the liver. When the live functions are compromised the most obvious symptom is yellowing of the whites of the eyes and skin.