"And". It should be such a simple word.
Particularly for something written in a time when women were often considered little, if at all, better than property, that verse from Genesis makes a fascinating assertion. The image of God is not the sole domain of the male, nor, for that matter, of the female. Neither masculine nor feminine is better or more Godly. The man cannot say to the woman that he is more favored of God, nor the woman say to the man that nothing of God is in him. All are part of God's creation and exhibit facets of God's nature.
Created "in the image of God... male and female". Not only does this make neither inferior, it leads to the inescapable conclusion that the image of God is itself neither purely male nor purely female. This God is both and neither. We might even say that God... transcends gender.