Athene albifacies (now Sceloglaux albifacies) - The Laughing Owl
This now-extinct owl of New Zealand was in a monotypic genus (meaning there was only one species in the genus), and was one of the most genetically distinct owls, having been isolated from other Strigidae for longer than any other genus.
Collection of the owls for museums, food, and predation by introduced animals led to their extinction sometime around 1912. Interestingly, these owls actually adapted surprisingly well to the intrusion of introduced species such as rats. They weren’t ground-nesters, so their eggs weren’t threatened by the fat Norway rats that were not as keen on climbing as other rats were, and the big rats made a fine meal for owlets. So really, their extinction was caused by direct predation by humans.
The Zoology of the Voyage of the H.M.S. Erebus & Terror, 1839-1843. John Richardson and J. E. Gray, 1845.