"At first glance, the smaller animal looks like a spider, but gripped…

"At first glance, the smaller animal looks like a spider, but gripped to the head of the Mozambican long‑fingered bat was actually a six-legged, wingless bat fly. This bloodsucking parasite moves around on its host, but usually sits on the lower back, out of reach. When a bat is in flight, the fly may sit on its host’s head instead"

https://www.nhm.ac.uk/wpy/gallery/2020-big-bat-bloodsucker?tags=ed.current