http://www.sararegistry.gc.ca/default.asp?lang=En&n=C0F414D2-1
"Qadri (1968) observed differences between aurora trout and brook trout in skeletal structure; in particular, the number of trunk vertebrate, the number of ribs with strongly bifid heads, the number of single neural spines and the total number of epineurals. There are also some morphometric differences, including the length of the maxillary.'
Are these not genetic differences?