Phpmyadmin and nginx

I have installed phpmyadmin and nginx. I just want to limit phpmyadmin access to my IP address. But when I look in nginx configuration, there is no settings or conf file for phpmyadmin and I still can access it. When I stop nginx than site is not availible, when I start it than I see phpmyadmin site. where is phpmyadmin setup to work with nginx if there is no setting wherever I look in /etc/ngix?