pacman: update archlinux-keyring to solve corruption

I recently ran an update which did fine except for...

error: udiskie: signature from "Ambrevar " is unknown trust
:: File /var/cache/pacman/pkg/udiskie-1.5.1-1-any.pkg.tar.xz is corrupted (invalid or corrupted package (PGP signature)).
Do you want to delete it? [Y/n] Y
error: failed to commit transaction (invalid or corrupted package)
Errors occurred, no packages were upgraded.

After attempting several fixes and checking Arch forums, I stumbled across this manjaro forum. Sure enough:

# pacman -S archlinux-keyring

Following this, it was a simple

# pacman -S udiskie

to catch it up.