serial port name

Hi I use a Mac OS X el Capitan with a R820T USB dongle. But I have the following problem. I can not find out which is my Serial Port Name: m-gs-computer:~ martin$ ls /dev/tty* /dev/tty /dev/ttysf /dev/tty.Bluetooth-Incoming-Port /dev/ttyt0 /dev/ttyp0 /dev/ttyt1 /dev/ttyp1 /dev/ttyt2...