Stephanofilaria okinawaensis n. sp. from cutaneous lesions on the teats of cows in Japan.

This is the first report on the occurrence of stephanofilarial sore on the teats of cows in the Nansei (South western) Islands, Japan, and on the taxonomical position of etiological parasites. Stephanofilaria worms were collected from cutaneous lesions of affected teats of cows in such proportion that the sex ratio of worms might be one male to three females. Morphological and anatomical observation was made on parasites suspended in lactophenol and by the scanning electron microscope. As a result, these parasites belonged to the same species as Stephanofilaria sp. Kono, 1965, which was previously reported to cause a strange type of dermatitis on the muzzle of cattle in the Nansei Islands. The description of Stephanofilaria sp. by Kono was reviewed. Subsequently, detailed comparison was made between those parasites and the other known species of the genus Stephanofilaria. It led to the establishment of a new species called S. okinawaensis Ueno and Chibana, 1977 after the name of the enzootic area.