This is a group of nematodes that contains eye worms of mammals and birds (Thelazia and Oxyspirura). Two of these eye worms, Thelaziacaliforniensis and Thelaziacallipaeda, have been reported from the eyes of cats. The Thelazioidea also contains a roup of morphologically related nematodes, the Pneumospiruridae, which are found in the lungs of mammalian hosts. Cats are infected by two species of the Pneumospiruridae, Vogeloidesmassinoi and Vogeloides ramanujacharii . Species of Thelazia use flies as their intermediate hosts. It is expected that members of the Pneumospiruridae also use arthropod intermediate hosts.