This is a Sprat 103 ultralight, it has no ailerons, and no ruddervator (on its v-tail). How then does it fly controllably?
The wing is split to two halves, each half is mounted on its own axis. By changing each half's angle of incidence (and thus angle of attack) changes the amount of lift generated by the relevant side.
See this video of a scale model.
A scheme of the mechanism