"Serranas" is a flamenco style, originated in Ronda area (Málaga). It was a kind of rural song, typical of the popular Andalusian folklore.
In 19th century, some singers performed this style in flamenco way, but keeping on this peasant atmosphere. Most important singer this style was "El Sota", who teach "serranas" to Antonio Chacón. Currently, "serranas" are played with guitar, following “seguiriya” rhythm.
It follows "seguiriya castellana", but this add a "trístico" (succession of three verses) with the same rhythm. As singing, it requires good singing skills because of its complexity. Furthermore, it's important to have an harmonious voice in order to temper and extend the "thirds".