豚尾叶猴（Simias concolor），又名猪尾叶猴，是一种笨重的旧世界猴，其长臂却很适合攀树。牠们的毛皮呈黑褐色，面上无毛而呈黑色。牠们是疣猴亚科下唯一尾巴较短的，尾巴只有15厘米长。牠们的吻短及指向上。牠们约长50厘米及重7公斤。牠们以往与长鼻猴一同被分类在长鼻猴属中。

豚尾叶猴只生活在明打威群岛中，尤其是在北巴盖及南巴盖。牠们是日间活动及栖于树上的，很少会走到地上。牠们以细小的群族生活，成员约有3-8只，包括一只雄猴、一只或以上的雌猴及牠们的幼猴。牠们主要吃叶子、果实及草莓。有关其繁殖的数据不详。

The pig-tailed langur (Simias concolor, monotypic in genus Simias) is a large Old World monkey, endemic to several small islands off the coast of Sumatra in Indonesia. Its face is black, its fur is blackish-brown and it has a relatively short tail. It is a diurnal species, feeding in small groups in the rainforest canopy on leaves, and to a lesser extent, fruit and berries. Little is known of its natural history, but it is heavily hunted, its populations have been declining rapidly and the International Union for Conservation of Nature has assessed its conservation status as being "critically endangered". It has been included on a list of the World's 25 Most Endangered Primates.