I was trying to express "Russian bear" in scientific terms.
Ursus would be the bear part of it. But I really couldn't figure out how to express Russia.
List of mammals of Russia gave me no hints.
I did see terms alluding to Siberia, as in sibirica. Canada - canadensis. Ursus americanus, etc... So terms that would not have known in Latin times have been "Latinized". I recognized nothing similar for Russia.
Rus or something like it would be my expectation and there were a number of names ending with it. Myospalax psilurus, Phodopus sungorus, Microtus obscurus... but I got the impression that these were more regular Latin word-ending syllables than denoting Russian-ess.
I also looked around for questions about "Russia" here. Nothing looked it answered the question. Google Translate left it at "Russian ursus".