Search

Megalobatrachonema nipponicum Yamaguti, 1941 (Nematoda: Cosmocercoidea: Kathlaniidae), the type species of the genus Megalobatrachonema, had been only once reported from the Japanese giant salamander, Andrias japonicus (Temminck, 1836) (Amphibia: Cryptobranchidae), in the last 80 years. Herein, we reported the present species from A. japonicus and hybrids (A. japonicus × Andrias davidianus (Blanchard, 1871)) following the original description. The examined specimens were morphologically identical to the original description. We showed the phylogenetic position of M. nipponicum among cosmocercoid species as well as among congeneric species, which suggested the polyphyly of the genus. In addition, the phylogenetic analysis did not support the subgenera in this genus. Thus, we considered the presence or absence of an esophageal bulb valve as a key morph to identify species, not subgenus, of Megalobatrachonema. [ABSTRACT FROM AUTHOR]

The first survey was conducted for helminth fauna of hybrid giant salamanders (hybrids between Andrias japonicus and other congeneric species), and introduced A. davidianus in Kyoto Prefecture, Japan. Three nematode species, Spiroxys hanzaki, Amphibiocapillaria tritonispunctati and Falcaustra sp., and one trematode species, Liolope copulans, were recovered from their alimentary canals. These results show that hybrid and introduced Andrias species are commonly infected with similar helminth species to those previously reported to infect A. japonicus. We conclude that the spillback of native parasites to introduced A. davidianus has occurred in Kyoto Prefecture. This study is also the first record of Falcaustra species parasitizing Andrias species in Japan. [ABSTRACT FROM AUTHOR]