This is something that's been bugging me for years, so I did a little investigating. In the early days of Western Sonic fandom it was common knowledge that "Nack the Weasel" went by the name "Fang the Sniper" in Japan, but it was still generally accepted that he was in fact a weasel, despite not really having any weasel-like features. If I recall correctly it was around 2002 that Western Sonic fandom became aware of Fang being half wolf, thanks to the now defunct Sonic Dimension fan site run by Japanese fan BULK. It was a veritable treasure trove of Japanese Sonic lore and information and BULK would often answer questions from English speaking fans, although his English was limited. I believe there was some confusion at the time about how Fang's species was listed on the Sonic Dimension profile. Either through language barrier miscommunication with BULK, or just plain assumption, we all just sort of settled on the idea of Fang being half wolf and half weasel. The wolf part explained the muzzle and the sharp tooth, so his design started to make a little more sense. I got thinking about this again earlier today and decided to search the Japanese Internet for any information on Fang. All the relevant results backed up Fang being a half-breed, half wolf specifically, but I kept getting weird auto-translations for the second species. I got in touch with a friend who knows Japanese and asked him about a sentence on the Japanese "Sonic & Tails 2" Wikipedia page. He translated it as: I then showed him the species listing on the old Sonic Dimension profile page. He said that from what he could tell, they had turned the two words (okami and tobinezumi) into a compound. This might have been the source of the confusion all those years ago. I asked my friend if he had any idea how Sega of America could have landed on weasel as his species. He said that it might be due to the association between rats and thieves not really being a thing outside of Japan. So in place of the "rat = thief" association they went with "weasel = weasely/devious". Anyway, here's what a jerboa looks like: Long ears. Long feet. Zig-zaggy tail. Known for being able to jump very high. And here's the kicker. That guy right there is specifically a four-toed jerboa. Fang only has four digits on each hand. Boom. The only mystery left is where the Japanese fandom actually got the species information to begin with.