Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. The Oak Yellow Underwing (Catocala nymphagoga) is a moth of the Noctuidae family. It is found in Southern Europe, from Bulgaria up to the Iberian Peninsula and sometimes further north as a migrant. It is also found in North Africa and Asia Minor.The wingspan is 35 43 millimetres (1.4 1.7 in). Adults are on wing from June to August depending on the location.The larvae feed on Quercus species. A moth is an insect closely related to the butterfly, both being of the order Lepidoptera. Moths form the majority of this order; there are thought to be 150,000 to 250,000 different species of moth (about ten times the number of species of butterfly), with thousands of species yet to be described.