The legend of the Cuco began to be spread to Latin America by the Portuguese and Spanish colonizers.
There is no general description of the Cuco, as far as facial or body descriptions.
The legend of the Cuco is widely used by parents in Spain and Latin America in order to make their children go to sleep. Parents usually tell small kids that the Cuco will take them away if they don't fall asleep early. This method has been in use for decades now.
Dominican Salsa-Merengue musician and singer Cuco Valoy makes several humorous references to the myth in some of his songs (¡ahi viene el cuco, mama!).
Puerto Rican musician Angel Peña's nickname is "Cuco", an allusion to the legendary myth.
In Brazil Cuco appears as a female, 'Cuca'. Cuca appears as the villain in some children books by Monteiro Lobato. Artists illustrating these books depicted the Cuca as an anthropomorphic alligator.
In Northern New Mexico, where there is a large Hispanic population, El Cuco is referred to in its Spanglish name, the Coco Man. His image is construed with Brazil's sack man; he carries a bag to take naughty children around Christmas time, and demands repentance in the form of Catholic prayers.
The Bogeyman (or boogeyman) could be considered an English equivalent of the Coco, since both monsters attack children who misbehave.
POPULAR SONG FOR THE COCO: duérmete mi niño, duérmete ya...por que viene el coco y te comerá (sleep my child, sleep now...or else comes the coco to eat you)
"El Cuento del Cuco", the Cuco Story in Spanish: http://hatillo_pr.tripod.com/elcuco.htm