These are the tell-tale signs of the Leaf Miner. There are many, named according to the plant they infest. A worm hatches from an egg laid on or in the leaf and burrows around inside the leaf consuming the chlorophyl-laden nourishment which leaves these un-green trails. Many are not so artistic as these in Trumpet Vine, but create blotches instead of trails.
After a few weeks, the worms drop to the ground. They burrow in to overwinter and emerge as winged creatures that lay eggs on preferred leaves, and start the whole cycle over again. They are not destructive enough to kill a healthy shrub. But annual attacks may weaken it to the point where it is more prone to disease atatck.
Miner-like markings have also been seen on various fruits. This Cherry Tomato is typical.
Could it be a Miner? Borers have been found inside Tomatoes doing their dastardly deeds.