Complex sentence: Black-and-white colobus are of Old World monkeys of the genus "Colobus" and are closely related to the red colobus monkeys of genus "Piliocolobus".
Split into simpler sentences: Black-and-white colobus are a genus of Old World monkeys. They are of the genus "Colobus" and are closely related to the red colobus monkeys of genus "Piliocolobus".