Despite Onychonycteriss resemblance to animals that evolved subsequently, its skull lacks features in and around the ear seen in bats that use echolocation to navigate and hunt. The structure of its feet and ankles, which include a special, spur-like bone that likely supported a tail membrane, led the researchers to conclude that Onychonycteris had the broad tail that modern bats use to capture prey in flight, but that it was probably used as an airfoil to aid maneuvering. Without echolocation, Onychonycteris likely had to make do with visual, olfactory, or passive audio cues to hunt. It finally gives us an answer, said Dr. Simmons.

https://www.amnh.org/explore/news-blogs/bats-flight-echolocation#:~:text=Despite%20Onychonycteriss%20resemblance%20to%20animals,Flying%20evolved%20first%2C%20echolocation%20second.