Looking like a cross between a dragonfly and a butterfly, owlflies (family Ascalaphidae) are in fact more closely related to ant lions and lacewings. These nocturnal predators feed on small insects that they catch on the wing. By day, they sleep concealed on twigs, or in this unusual case (Cordulecerus sp.), as a group together on a root hanging above a stream. Sleeping in an aggregation with their antennae held outstretched in a perimeter may help to better detect the approach of predators, keeping the group safer than sleeping alone. Yasuní National Park, Ecuador.