any sucking bugs on the reverse of the leaf ???

ken

It sure looks like a mosaic virus, to me. Does the leaf feel a little bit leathery, different from the others?

Have you observed any aphids on the beans?

I don't want to definitively tell you that this is one of the bean mosaic virus diseases from just one distant picture......but I would sure be suspicious from that type of mottling.

I don't see any bugs I don't recall the leaf feeling strange - here are some closer up pics

I will yank them when I get home to be safe - should I remove only plants with visible mottling or assume the whole area is infected?

and a pic of the front

Ditto on the virus diagnosis. Remove the affected plant.