I've had this caterpillar identified at Lepiforum e.V. They said it's a Gymnoscelis rufifasciata, a Double-striped pug. I took a photograph of an adult Gymnoscelis rufifasciata moth in 2016. This caterpillar was very purple and very small.
<a href="//commons.wikimedia.org/wiki/User:Stanzilla" title="User:Stanzilla">Stanzilla</a>
CC BY-SA 4.0
<span class="int-own-work" lang="en">Own work</span>