Two hitching a ride on a Spined Oak Borer (Elaphidion mucronatum). Beetle record here: https://www.inaturalist.org/observations/225318656
Edit: 3 July 2024 added microscope pictures from collected specimens
This observation is for the fish! For the heron, see: https://www.inaturalist.org/observations/159918876
Complete metamorphosis from nymph to adult form
iNat is suggesting brown headed cowbird, but I was thinking young red winged blackbirds. Two individuals hanging out together, very unconcerned by my presence.