pg_stat_activity's client_addr column contains "::1" but actually comes from elsewhere?

Hello! I'm trying to track down where some connections are coming from. "select pid,client_addr,client_hostname from
pg_stat_activity"shows multiple entries with values with client_addr = "::1". "client_hostname" is blank for all
entries,by the way, and unhelpful in this scenario. Also, "state" is "idle" for these entries I'm interested in, in
casethat matters. 

::1 would imply the IPv6 loopback address, so that means the connection is coming from a process on the server, right?
ButI'm positive there is no process on this server that is connecting to PostgreSQL (other than my psql session). 

So where are they actually coming from and why is PostgreSQL seemingly misreporting them as coming from ::1?

Thanks for any help,
Ed