There may be two subspecies of the Siamang. If so, they are the nominate Sumatran Siamang ("S. s. syndactylus") and the Malaysian Siamang ("S. s. continentis", in peninsular Malaysia). Otherwise, the Malaysian individuals are only a population. The Siamang is the only gibbon which occurs sympatrically with other gibbons; its two ranges are entirely within the combined ranges of the Agile Gibbon and the Lar Gibbon.