Macaroni penguin been considered separate species, but the close similarities of their DNA sequences has led some, such as the Australian ornithologists Les Christidis and Walter Boles, to treat the royal as a subspecies of the macaroni. The two species are very similar in appearance; the royal penguin has a white face instead of the usually black face of the macaroni. Interbreeding with the Indo-Pacific subspecies of the southern rockhopper penguin ("E. chrysocome filholi") has been reported at Heard and Marion Islands, with three hybrids recorded there by a 1987–88 Australian National Antarctic Research Expedition. The macaroni penguin is a large, crested
Macaroni pie (and optionally onion) is added, thus creating a "lihamakaronilaatikko" (literally, meat-macaroni casserole). The casserole may be topped before baking with breadcrumbs and grated cheese and/or knobs of butter, to form a crunchy crust. "Makaronilaatikko" is typically served with tomato ketchup and pickles such as gherkins. Pastitsio is a type of macaroni pie in Greek cuisine prepared using elbow macaroni noodles and various additional ingredients. In Italian cuisine the macaroni pie () is a traditional dish in several cities, with a long tradition originating from the "pastizzi" prepared by the chefs active in the Italian courts of the Renaissance: the most