Outsider, You are correct in stating that a buffalo is a different animal, but the fact is that American Bison are commonly called buffalo even though they technically aren’t. Beefalo is a domestic cattle/Bison hybrid
Re dogs. All domestic dogs, coyotes, dingos are, in fact, genetically wolves.
I have raised this issue with our local Rav. Is conventional taxonomy and halachic taxonomy the same? If animals don’t resemble one another are the different minim, even though they are the same species according to conventional taxonomy? Are juvenile forms a different min than adult forms? As stated above, a great dane and a dachshund are taxonomically identical, are the different minim al pi halacha?