PGP Key importing during repomd checking

Hi all,

I'm setting up a repository for distributing third party content, and
only the repomd.xml file is signed.  Thus we are configuring the
corresponding .repo file with:

repo_gpgcheck=1
gpgkey=file:///etc/pki/rpm/myrepokey.pub.asc

When running 'yum makecache' for the first time, it ask for
confirmation when importing the pgp key from the configured file, and
everything is fine so far.  But when I want to erase the key it
doesn't show up with 'rpm -qa gpg-pubkey*'
Question is:  in which keychain is this key being imported? I went
through the code but couldn't figure it out...

Thanks in advance.

saludos
daniel