DAO 56:65-74 (2003)  -  doi:10.3354/dao056065

Parasitism by Dermocystidium ranae in a population of Rana esculenta complex in Central Italy and description of Amphibiocystidium n. gen

. R. Pascolini1, P. Daszak2,*, A. A. Cunningham3, S. Tei1, D. Vagnetti1, S. Bucci4, A. Fagotti1, I. Di Rosa1

1Department of Cellular and Molecular Biology, University of Perugia, Piazza dell¹Universita, 1, 06100 Perugia, Italy
2Consortium for Conservation Medicine, 61 Route 9W, Palisades, New York 10964, USA
3Institute of Zoology, Zoological Society of London, Regent¹s Park, London NW1 4RY, United Kingdom
4Department of Physiology and Biochemistry, University of Pisa, Lungarno Pacinotti, 43, 56124 Pisa, Italy
*Corresponding author. Email:

ABSTRACT: We report the enigmatic parasite Dermocystidium ranae in a green frog population (Solomeo, Umbria, Italy) of the Rana esculenta complex, consisting of the parental species R. lessonae (L) and hybrid form R. esculenta (E). In this population a rapid 50% decline of the parental form L was observed. Large dermal U-shaped cysts of D. ranae were found primarily on the ventral aspect of infected individuals, with a significantly higher incidence of infection in the parental species compared to the clonal hybrid. In each form, however, there was little pathological change associated with infection, and the cause of the recent declines of R. lessonae at this site remains unknown. In this paper we present the first ultrastructural description of an amphibian Dermocystidium sp. and we review the taxonomy of Dermocystidium, Dermosporidium and Dermomycoides spp. from amphibians. We conclude that Dermosporidium multigranulare Broz & Kulda, 1954 is synonymous with Dermocystidium ranae Guyénot & Naville, 1922 and, due to lack of sufficient differences between genera and significant dissimilarities with fish Dermocystidium spp., the 3 amphibian genera are synonymous. We propose that they should be designated to a new genus, Amphibiocystidium n. gen., and Dermocystidium retained for those species parasitic in fish.

KEY WORDS: Amphibian · Rana · Dermocystidium· Amphibiocystidium · Amphibian declines

Full text in pdf format