Helminths of the American Toad, Anaxyrus americanus americanus, and Fowler's Toad, Anaxyrus fowleri from the Silver Creek Area and Lake Michigan Shoreline in Western Michigan, U.S.A.

摘要

In total, 105 toads (71 American toads, Anaxyrus americanus americanus Holbrook, 1836; 31 Fowler's toads, Anaxyrus fowleri (Hinckley, 1882); and 3 A. a. americanus X A. fowled hybrids) were collected in 2011 and 2012 from the lower Silver Creek area and Lake Michigan shoreline (LMS) in western lower Michigan and examined for helminths. Five helminth species (1 Digenea, Gorgoderina sp.; 1 Cestoda, Mesocestoides sp.; and 3 Nematoda,-Cosmocercoides variabilis, Oswaldocruzia pipiens, and Rhabdias americanus) were found in American toads. Mesocestoides sp. and R. americanus were the most common helminths of American toads. Four helminth species (1 Digenea, Haematoloechus sp.; 1 Cestoda, Mesocestoides sp.; and 2 Nematoda, C. variabilis and 0. pipiens) infected Fowler's toad, with Mesocestoides sp. being most common. Anaxyrus a. americanus X A. fowleri hybrids were infected with Mesocestoides sp., R. americanus, and C. variabilis. The prevalences and intensities of helminth species found in both toad species and the mean numbers of helminth species in infected toads and in all examined toads were always higher in American toads than in Fowler's toads. Although C. variabilis and R. americanus infected American toads and C. variabilis and O. pipiens infected Fowler's toads on the LMS, it is believed that they were not infected there. The occurrence of these nematodes in toads on the LMS reflects infections that occurred in their breeding ponds and other moist areas. This is the first survey on the helminths of Fowler's toads from Michigan and from a shoreline dune area for both toad species.