The male Long-tailed Widowbird (Euplectes progne) has exceptionally long tail feathers roughly half a meter in length.
Friedrich Boie was the author of several bird species and the hummingbird genus Glaucis, the swallow genus Progne, the cuckoo-shrike genus Minivet, the passerine genus Lipaugus, the owl genus Athene and among other genera the genus Chrysococcyx.