When I see spiders and ladybugs on my plants, I figure there must be something there for them to eat. Otherwise, they'd move on. And often, I see some little mealies or aphids that they are feasting on.

I don't grow this particular plant and I don't see where aphids or mealies would hide on/in it. It sure does look like something is munching on your plant! Do you happen to have snails or slugs coming out at night? Or a rodent - rat, chipmunk, etc.?

I hope some more folks chime in because I wasn't very helpful. 8-)

The simple answer is no, that spider didn't take a bite out of your plant. Spiders don't eat plants - they eat bugs.

Here, that sort of bite or chunk of missing tissue would be due to a snail or slug. That happens to mine from time to time when they get moved outside for the summer even though I bait for the critters and the plants are kept elevated. I swear they descend from above!!