The Gemara says that we say the bracha of meshaneh habrios on three animals - elephants. monkeys and kifuf which many commentaries say is an owl. The Rif, Rambam and Rosh all bring this Gemara down with all three animals but the Tur and the Shulchan Aruch miss out the kifuf - I was wondering why.
Rav David Yosef Shlita in Halacha Berurah says that there is a machlokes as to what a kifuf is - he sends you to a Rashash on the Gemara who brings a different girsa - that it is a kipod which is a hedghog. Rav Yosef says that because there is a safek as to what this animal is we do not say it even on an owl becuase of safek brachos lehakel - do you know of any other discussion on this question?
Yehonasan Gefen, Ramat Beit Shemesh
From the very fact that Rashi had to define for us what a Kipuf is (on Daf 57b -- not 58b, where it is referred to as Kipufa) means that it is not clear to us what a Kipuf is, as oppsosed to a Pil and a Kof which need no explanation. Therefore, there was no reason for the Shulchan Aruch to mention it. The Shulchan Aruch was only trying to bring clear examples (as examples should always be) of where one would say the Berachah. He was not trying to teach us something about these animals. If there was a Mitzvah that somehow involved a Kipuf, then the Shulchan Aruch would have no choice but to mention it and define what it is. In the times of the Tana'im, it seems that it was obvious to everyone what a Kipuf is, so it was chosen as an example to be used in the Beraisa.
I could not find any other discussion among the Mefarshim about the identity of the Kipuf.