It may be a polyswitch. I've seen some polyswitch (also known as resettable fuse) in a very similar shape and color. Also on a similar board next to a nickel spark gap, as in your pic.
If you pry the yellow coating off, you will be able to recognize it by look. An MLCC will be solid, ceramic, and if you hit it, maybe you can break it. A polyswitch will be soft, almost like plastic, with a few metal foils where the legs are welded onto it.