It is oriented horizontally and extends posteriorly from the pterion (Pterion is the region as indicated in the figure above, that is the meeting point of the frontal, parietal, temporal and sphenoid bones). The suture continues posteriorly as the petromastoid suture.
Some consider the posterior part the squamous suture as a separate suture called additamentum posterius suturae squamosae because of its serrated appearances in most of the humans.