https://serverfault.com/questions/766506/automount-usb-drives-with-systemd#804212

there is a new, succinct systemd auto-mount option which can be used with fstab which allows you to use all the standardized mount permission options, and it looks like this:

  x-systemd.automount

an example of it in an fstab line:

  /dev/sdd1   /mnt/hitachi-one     auto     noauto,x-systemd.automount     0 2

the noauto option will mean it will not attempt to be mounted at boot, as with older software autofs.

after adding a new x-systemd.automount line to fstab you then need to run:

  sudo systemctl daemon-reload

and then both, or one, of the following:

  sudo systemctl restart remote-fs.target
  sudo systemctl restart local-fs.target

for more infomation about it:

https://wiki.archlinux.org/index.php/Fstab#Automount_with_systemd