Ensign Wasp waves its abdomen like a flag

This Ensign Wasps, in the family Evaniidae, was filmed in the Amazon rainforest of Ecuador. The black abdomen (metasoma) moves up and down as if signalling with a flag, which gave rise to the common name ensign wasp. They are completely harmless to humans and actually are beneficial since they lay an egg in the egg cases of cockroaches and the hatched wasp larva feeds on the roach eggs.