This is a Package extension. There are extensions installed on your site which claim to belong to this package –their package_id points to it– but they are not mentioned in the package's own XML manifest.
This is the mirror image of the Missing Package Children issue. Instead of the package's manifest listing extensions which are not installed, the database has extensions claiming to be installed by the package which the package's manifest no longer mentions.
This usually means the extensions in question used to be part of an older version of the package but have since been removed from it, i.e. they are obsolete. Since they are no longer part of the package they no longer receive updates through it, and future updates of the package may not account for their continued presence, potentially causing conflicts or unexpected behaviour.
First, try to reinstall this package twice in a row, without uninstalling it before or in between. It is possible that Joomla! previously failed to update the XML manifest to a newer version. If that's the case, Joomla! (and Onthos) would not be aware that extensions included in the newer version of the package actually do belong to it. The double reinstallation fixes this problem.
If this didn't help, the extensions appearing as belonging to the package are most likely obsolete, i.e. they used to exist in a previous version of the package but are no longer included in it. If this is the case, you will need to remove them.
Joomla! does not automatically remove obsolete extensions which are no longer included in a newer version of a package. The developer has to write custom code to do that, typically in the package's installation script. If that code did not run, had a bug, or if you restored your site from a backup taken before the removal took effect, you may end up with the obsolete extensions left behind. Since these extensions no longer receive updates they should be removed to ensure the security and stability of your site.