I accept, it is not alien, Gomphocarpus, it is native to South Africa and common in New Zealand, but look at them. Aren't they bizarre?
I love to use them in Ikebana, they are so interesting, especially if you remove all the leaves and left with this balloon like structures.
After a few days later though, these open up and the seeds could fly away in all directions so it is better to cut the opening folliciles at home.