Leptosomus discolor; Print; The cuckoo roller or courol (Leptosomus discolor) is the only bird in the family Leptosomidae; which was previously often placed in the order Coraciiformes but is now placed in its own order Leptosomiformes. Its nearest relative is not clear. Morphological evidence may suggest a placement in or near to Falconiformes. In the rather comprehensive DNA study by Hackett et al; this and the hoatzin are the only two birds whose position is unclear; although the cuckoo roller seems to be at the root of a group that contains the Trogoniformes; Bucerotiformes; Piciformes; and Coraciiformes.; 1700-1880