I think Morena might just be the name of a dance or song, maybe in Spanish? Something like that. Can't really identify your particular guitar but you might like to have a look at this link anyway. Is it an Artista 'Morena' or is the
brand actually called Morena. Whatever it is, it was certainly designed to use nylon strings, of that I'm sure. Why don't you take it to a reputable dealer and get it looked at with a view to having the strings renewed, (not a very big investment) and it's playing condition appraised?
http://www.activemusician.com/item--MC.MORENA