Yamanba: (Retired) (199?-2004)(meaning mountain ghost hag)(3rd picture, girl on far right) is a style mostly to shock people, and rebel against the geisha/bihaku stereotypes. As well as the other types of tanning gals. (Some gals just like to tan.) Unlike manba there nose stripe goes past the eyebrows from what I hear. Pretty close in looks to manba though.
Tan scale: 1 2 3 4 5 6 7 8 9 10
Dark tans, white lipstick, white eye make-up, stickers below the eyes, circle lenses, bright clothing, tons of accessories, Hawaiian themed clothes, straw cowboy hats, hibiscus flower leis.
(that picture is newer, but its only one I could find that the nose stripe goes past the eyebrows.)(Cause alot of the pics out there are just manba)
Depending on the text and translator, the Yamauba appears as a monstrous Crone, “her unkempt hair long and golden white … her kimono filthy and tattered,” with cannibalistic tendencies.  In one tale a mother traveling to her village is forced to give birth in a mountain hut assisted by an apparent kindly old woman, only to discover, when it is too late, that the stranger is actually Yamauba with plans to eat her newborn child.  In other story the yōkai raises the orphan hero Kintarō, who goes on to became the famous warrior Sakata no Kintoki. 
Yamauba is said to have a mouth at the top of her head under her hair.  In one story it is related that her only weakness is a certain flower containing her soul. 
Even japan has its own tanning culture, just like America has a few of its own. This style is NO way mocking African people.
If some has something to add or tweak feel free to contact me politely, or you will be ignored.