Graduate School of Science, Kobe University, 1-1 Rokkodai, Nada Ward, Kobe City, Hyogo Prefecture, 657-8501, Japan.
Setouchi Parasite Biodiversity Laboratory, 3-2-20-103, Ushita-Honmachi, Higashi Ward, Hiroshima City, Hiroshima Prefecture, 732-0066, Japan.
Syst Parasitol. 2021 Jun;98(3):307-319. doi: 10.1007/s11230-021-09979-z. Epub 2021 Apr 19.
A new gyrodactylid species, Gyrodactylus ajime n. sp., is described from the skin and fins of an endemic and commercially important loach Niwaella delicata (Niwa) (Cypriniformes: Cobitoidea: Cobitidae), from the upper reach of the River Yura in Ashiu, Kyoto Prefecture, Japan with scanning electron microscopy observations and molecular data. This species can be distinguished from congenerics by characteristics of the sickle of the marginal hook: the sickle proper is composed of two straight sections and a curved section; its short point extends beyond the limit of the toe and is directed downwards; and the upper corner of heel angular is slightly raised. There are 31 species and subspecies of native loaches (Cobitoidea) known from Japan, of which 25 are red-listed nationally, and two are commercially important. I reviewed all reports of monogeneans from Japanese loaches, and found that only five fish species have been recorded as hosts of these parasites. This suggests that the parasite fauna of these fishes is poorly described. It is urgent to thoroughly describe the monogenean parasites of loaches in Japan as some of the parasite species may be threatened with co-extinction because their hosts are threatened, and to understand any negative impacts on commercially important fish species.
一种新的旋口科鱼虱，Gyrodactylus ajime n. sp.，是从日本京都府绫部市有浦川上游的一种地方特有且具有商业重要性的泥鳅 Niwaella delicata（Niwa）（鲤形目：泥鳅科：泥鳅科）的皮肤和鳍上，通过扫描电子显微镜观察和分子数据描述的。该物种与同属种的区别在于边缘钩镰的特征：镰本身由两个直段和一个弯曲段组成；其短点超出了趾的限制，并向下指向；而跟角的上角则略微抬起。日本有 31 种和亚种的本地泥鳅（泥鳅科），其中 25 种在全国范围内被列为红色名单，两种具有商业重要性。我回顾了所有关于日本泥鳅单殖吸虫的报告，发现只有五种鱼类被记录为这些寄生虫的宿主。这表明这些鱼类的寄生虫区系描述得很差。迫切需要彻底描述日本泥鳅的单殖吸虫寄生虫，因为由于其宿主受到威胁，一些寄生虫物种可能面临共同灭绝的威胁，并了解对商业上重要的鱼类物种的任何负面影响。
