The little lines are an area where a little more rubber is to provide some extra structural integrity along the tire bead.

Often, a tire will mount similar to what you've pictured, then when you inflate the tube it will pop into place (usually with a "POP" sound). If you're at pressure, worst cast is most likely to be that the tire runs a little out of round and will increase wear. Not really a higher risk of a blowout or puncture, other than perhaps a pinch flat.

If I were faced with this mount, I would drop the tire pressure significantly to where the tire is easily moved and adjust the bead before reinflating.