A PARASITE. MYXOBOLUS HYLAB. Sp. Nov.. OF THE REPRODUCTIVE ORGANS OP 

 THE GOLDEN SWAMP FROG, HYLA AUREA. 



By T. HARVEY JOHNSTON, M.A . D.Sc, and M. J. BANCROFT., B.Sc. Walter and Eliza 

 Hall Fellow in Biology, University, Brisbane. 



(Plato XIV. ; text ligs. 1-5.) 



A NUMBER of Golden Swamp Frogs. Hyla aurea, which were received from Sydney during 191 5 lor 

 dissection purposes in this laboratory, wire found to have their genitalia infested by a species of 

 Myxobolus. This material forms the subject matter 01 the following paper, though in addition to 

 some preparations made at that time, we have also others made many years previously in Sydney. 



The first tii record the occurrence of this parasite was A. \V. Fletcher, who presented a paper to 

 the first meeting ol the Australasian Association for the Advancement of Science in 1888. an abstract 

 of which was published in it-. Report. Fletcher used the wide term " myxosporidium," but his de- 

 scriptions leave no doubt that he was dealing with the -amr organism as we are discussing. The 

 parasite was observed in a considerable proportion of the male frogs dissected in the Biological 

 Laboratory of the University of Sydney, and was observed in one species only. Hvlti aurea. It was 

 said to have been found also in the urinary bladder under the peritoneum of both males and females, 

 as well as in the testes. Fletcher aptly described the appearance of the infected part as presenting 

 ' a large oolitic mass of encysted myxosporidia," and he gave a short account of the spores which he 

 described as closely resembling those oi a species occurring encysted on the gills of cyprinoid fish. 

 Several intermediate stages iu, the development of the spore were observed. 



The myxosporidium which Professor W. A. Haswell (1890, p. 661) mentioned as being common 

 in Hyla aurea is obviously the same parasite. The only other records of this protozoon were made by- 

 one of us (T. H. J., 1909) who referred to Myxobolus sp., a sporozoon infesting and destroying the 

 genital organs of Hyla aurea in Sydney, and by Cleland and Johnston (1910) in their paper on the 

 Haematozoa of Australian Batrachians," where mention was made of its occurrence in that frog in 

 the Sydney district. H. aurea does not occur in south-eastern Queensland, but is extremely common 

 in the neighbourhood of Sydney. 



The parasite is an interesting one, being the first member of the family Myxobolidae to be recorde 

 from an amphibian host. Representatives of each of the other families of Myxosporidia are knowd 

 as parasites of Amphibia. In addition, a microsporidian, Plislophora danilewskyi, Pfeiffer, has been 

 recorded from the foot-muscles of a European frog, Rana temporaria. We append a list of Myxn 

 sporidia known to infest members of the class Amphibia. 



Labbe (1899, pp. 87-95) mentions : — 



(1) Leptotheca ohlmacheri Gurley, as occurring in the kidney and ureters of Bufo lentiginosus 

 Rana esculenta, and R. temporaria. 



(2) Cystodiscus immersus Lutz ( = Sphaeromyxa immersa), in the gall bladder of Bufo marinus ' 

 and Leptodactylus ocellatus — both Brazilian batrachians. 



