In the night several owls, owlets, nightjars, etc. The owlet-nightjars are small nocturnal birds related to the nightjars and frogmouths. Wintering European nightjars in Africa may overlap with the related rufous-cheeked and sombre nightjars. Potoos are a group of large near passerine birds related to the nightjars and frogmouths. This physiological adaptation shows in nearly a hundred other species, including owlet-nightjars, nightjars, and woodswallows. Only a few birds, such as the nightjars, hunt nocturnal lepidopterans. The frogmouths are a group of nocturnal birds related to the nightjars. The oilbird is a slim, long-winged bird related to the nightjars. Unlike the closely related nightjars, the potoos lack rictal bristles around the mouth. The eyes are large, even larger than those of nightjars. Chuck-will's-widow has a short bill and a long tail typical of the nightjars. Also see a list of nightjars, sortable by common and binomial names. They resemble upright sitting nightjars, a closely related family (Caprimulgidae).