Pathological changes in African hyperoliid frogs due to a myxosporidian infection with a new species of Hoferellus (Myxozoa).

A proliferous, polycystic and sometimes fatal kidney disease due to an infection with myxosporidia is reported in 24 of 28 hyperoliid frogs (Afrixalus dorsalis, Hyperolius concolor, Hyperolius sp.) from Nigeria, Ghana and Tanzania. In line with pathological changes in fish, the disease is described as 'frog kidney enlargement disease' (FKED). Myxosporidian plasmodia, different developmental stages and spores occurred in the kidney, ureter, and urinary bladder and in the intestine of the frogs. The parasite belongs to the genus Hoferellus and is presented as a new species: H. anurae n. sp. Spores are similar in size and structure to other Hoferellus species in fish but differ by the presence of a more prominent suture line and shorter caudal appendages. This is the first report on a Hoferellus species in amphibians as well as the first report of the genus Hoferellus in African vertebrates.