ABSTRACT
Brachylaemidiasis is caused by members of the family Brachylaemidae Joyeaux and Foley, 1930. Brachylaemids are parasites of birds and mammals. The family Cyclocoeliidae Kossak, 1911 comprises parasites in the body cavity, air sacs, trachea, or nasal cavity of birds. There are two subfamilies. They are Typhlocoelum and Tracheophilus. Species belonging to Typhlocoelum genus have the genital pore pharyngeal or prepharyngeal, and the testes are not separated one from the other by the uterine coils. The testes are strongly lobed, are oblique, and are situated in the posterior part of body. In members of Tracheophilus genus, the genital pore is prepharyngeal, the testes are round, and the uterine coils pass in between the testes. The genotype is Tracheophilus sisowi Skrjabin, 1913, which was recovered from the trachea of several species of ducks in the U.S.S.R., France, other parts of Europe, and on Taiwan. The body of species belonging to Cyclocoelum genus are lanceolate to linguiform.
