For many years, there was a bit of debate about how many Lynx species there were. In the 1980s, the Canadian lynx and the Eurasian lynx were thought to represent a single species.
The Canada lynx is not a northern bobcat, as one might think. These cats are very similar to each other in size, and it actually gets quick touchy trying tease apart historical accounts of bobcats and lynx in North America.
But bobcats come from earlier invasion of the Lynx lineage that came into North America between 2-5 million years ago. The Canada lynx came about when an ancestral Eurasian lynx came into North America within the past 200,000 years. The Canada lynx is more closely related to the modern Eurasian lynx than to the bobcat.
Compared to the bobcat and Eurasian lynx, the Canada lynx is a bit weird. Eurasian lynx and bobcats are very much generalist predators. The Canada lynx is a super specialized predator. They pretty much live on snowshoe hares alone, and their populations track the snowshoe hare population cycles. It is pretty weird that this animal has hitched itself to such a tenuous prey species.
One could make the case that the Canada lynx is nothing more than a specialized Eurasian lynx, even though it is significant smaller.
I think this is a bit hard to justify. For one thing, there is absolutely no gene flow between Eurasian lynx and Canada lynx, except in captivity. Canada lynx, bobcats, and Eurasian lynx all can interbreed and produce fertile offspring, but unless the Bering Land Bridge appears again, there is no way for Eurasian lynx to arrive to hybridize with them.
I also don’t think there is any way to get around the super-specialized body of the Canada lynx, which is long-legged and big-pawed. It’s also a lot smaller than the Eurasian lynx.
So I think it is hard to get around the simple fact that this animal is distinct enough to be a species, even it can hybridize with bobcats and Eurasian lynx.