Two Unknown Marine Species of the Genus Diphyllobothrium from Human Cases

Abstract

The morphological haracteristics oftwo unknown marine species of the genus Diphyllobothrium were recorded. A cestode spontaneously expelled from a 27-year-old seaman resembled D. cameroni Rausch, 1969 from a Japanese seaman by Kamo et al. (1981) in the external morphology, but was different in the relative position of the uterine pore. It was related to D. hians (Diesing, 1850) in the position and shape of the cirrus sac, and in the relative position of the cirrus sac to the seminal vesicle, but was different in the shape and size of the scolex. Another cestode expelled after treatment with kamala from a 50-year-old seaman resembled D. hians in the shape of proglottids, the development of inner longitudinal muscle layer , the position of genital atrium, the uterine loops, and egg-sizes. This was rather related to D. elegans (Krabbe, 1865) in the shape and position of the cirrus sac and the relative position of the cirrus sac to the seminal vesicle, and was different from D. hians in these characteristics . The definite identification should be established in the future on the basis of more detailed materials and methods. INTRODUCTION Sakaguchi et al. (1971) have reported five human cases infected with diphyllobothriid cestodes found from the inhabitants of fishing villages in Nagasaki Prefecture, Japan. Three of those cestodes had been identified as Diplogonopurus grandis, while the remaining two had been taxonomically indeterminable. Later Kamo et al. (1979) observed the densely distributed deep pits of their eggshell surfaces by the use of scanning electron microscope, suggesting their association with marine environments. Since Kamo et al. (1977) suggested the occurrence of human infection with a certain species of Diphyllobothrium of marine origin, a few marine species of the genus Diphyllobothrium have been recorded from human cases in Japan such as D. yonagoense by Yamane et al. (1981), D. cameroni by Kamo et al. (1981), and D. pacificum by Kamo et al. (1982). The morphological characteristics of both specimens under consideration were different from those known species of marine origin in Japan. Moreover, they were not identical with descriptions of any other known species from marine mammals. Then their morphological characteristics were recorded here for further comparison and identification. 1 Department of Medical Zoology, Tottori University School of Medicine, Yonago 683, Japan 2 Department of Parasitic Diseases, Kumamoto University Medical School, Kumamoto 860, Japan

Cite this paper

@inproceedings{Kam2010TwoUM, title={Two Unknown Marine Species of the Genus Diphyllobothrium from Human Cases}, author={H M Kam and S. Yazaki and SOJI FUKUMOT and J Maejima and Yuji Sakaguchi}, year={2010} }