Calatheas (Prayer plants) are known for their bold patterned foliage. The leaves of most Calathea varieties fold up slightly during the night time due to nyctinastic movement, revealing the often colorful undersides of their striking leaves. Calathea Rattlesnake (Calathea Lancifolia) has long and narrow leaves with ruffled edges. They are bright green with alternating dark-green markings and a purple underside.