Hylobates syndactylus, commonly known as the Siamang, is a species of gibbon native to Southeast Asia. This primate is known for its black fur and unique vocalizations that sound like a deep and resonant boom. The Siamang is also known by a variety of synonyms, including the black-handed gibbon, the lesser siamang, and the symphalangus syndactylus. These different names refer to the same species of gibbon with slight variations in meaning and context, but they all describe the same fascinating and beloved primate found in the dense forests of Indonesia, Malaysia, and Thailand.