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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]

The transmission of adult parasites from prey to predatory hosts has been demonstrated for some acanthocephalan and one cestode species. Derogenes lacustris (Digenea: Hemiuroidea: Derogenidae) is a generalist parasite that infects, as an adult, the stomach of native and introduced freshwater fishes in Andean Patagonia. In the present work, the post-cyclic transmission of D. lacustris from native Galaxias maculatus (Galaxiidae) to introduced Oncorhynchus mykiss (Salmonidae) was proved experimentally. The observed transmission rate for this experimental infection was 19%. The body length of D. lacustris on day 14 post-infection was significantly greater than before transmission. The number of eggs also increased significantly after transmission, showing that D. lacustris can survive, grow and continue with egg production for at least 2 weeks in predatory salmonids. This study provides the first experimental evidence of post-cyclic transmission of trematodes and the results suggest that post-cyclic parasitism enables this species to broaden its range of hosts and distribution ranges in Argentinean Patagonia.

In this study, digital-optical computational imaging is proposed for object data transmission with a capability to achieve end-point logic operations over free-space data transmission. The framework is regarded as an extension of computational imaging using digital-optical codes originally developed for digital optical computing. Spatial code patterns for optical logic operations are extended to digital-optical codes in the temporal and spectral domains. The physical form of the digital-optical codes is selected, as appropriate, for the situation in use, and different forms can be combined to increase the data-transmission bandwidth. The encoded signals are transferred over free space and decoded by a simple procedure on the destination device, thus enabling logic operations at the end-point of the data transmission. To utilize the benefits of digital processing, a data-transfer mode is introduced which assigns preprocessing for the signals to be encoded and the end-point processing. As a demonstration of the proposed method, an experimental testbed was constructed assuming data transmission from sensor nodes to a gateway device appearing in the Internet of Things. In the experiment, encrypted signals of the sensor nodes, which were encoded by spatial digital-optical codes on RGB channels, were captured as an image, and the original signals were retrieved correctly by an end-point exclusive OR operation.