Theophilus is the shadowed crater just below the mid-part of the terminator. The dark hexagonal structure to the right is Mare Crisium, a basalt covered region.
Tycho is the bright complex crater towards the south with a bright ray system of ejecta.
There is a nice row of six craters just to the right of the terminator – from North to South,
1. Ptolemaeus flat crater filled with lava
2. Alphonsus (contains a dark halo zone of lunar volcanism)
3. Arzachel complex crater with central peaks and terracing.