Tactical map questions

There are symbols on the tactical map that I do not understand. First, sometimes there are glowing white areas with a symbol of a head with stars around it. These disappear when a soldier stands on them, but I can’t tell what, if any, effect occurs. Second, what are the red monster-type icons near the edge of the map? Spawn points?

for the white heads: these recover some WP of your team

The red monster skulls are where enemy reinforcements can spawn from