A Checklist of the Parasites of Ayu (Plecoglossus altivelis altivelis) (Salmoniformes: Plecoglossidae) in Japan (1912-2007)

1912～2007年の96年間に出版された文献に基づき, 日本産アユPlecoglossus altivelis altivelisの寄生虫に関する情報を寄生虫-宿主リストに整理して目録を作成した。本目録には, 29種の寄生虫(微胞子虫類1種, ミクソゾア類1種, 吸虫類13種, 単生類3種, 条虫類1種, 線虫類1種, 鉤頭動物3種, カイアシ類4種, エラオ類2種)に加えて, 学名がまだ決定していない寄生虫の情報が含まれる。寄生虫-宿主リストでは, 各寄生虫は高位分類群ごとに配列され, 最新の学名, シノニム, 寄生部位, 地理的分布および報告者の情報が示されている。アユの亜種, リュウキュウアユPlecoglossus altivelis ryukyuensisからは寄生虫の記録はない。ミクソゾア類のMitraspora plecoglossiをHoferellus属に移すとともに, ハスコウトウチュウAcanthocephalus opsariichthydis Yamaguti, 1935の学名が動物命名規約に則って正しい綴りと命名年であることを確定した。また鉤頭動物のEchinorhynchus oblitusをカジカコウトウチュウEchinorhynchus cottiのシノニムとした。

The ayu or sweetfish Plecoglossus altivelis altivelis is distributed in many rivers and some lakes in Japan and also occurs in rivers of the Korean Peninsula and along the east coast of China and northern Vietnam. In Japan, this species is one of the most important freshwater fishes for commercial fisheries, aquaculture, and recreational fishing. In the present paper, information on the protistan and metazoan parasites of ayu in Japan is compiled based on the literature published for 96 years between 1912 and 2007, and the parasites, including 29 named species and those not identified to species level, are listed by higher taxon as follows: Ciliophora (no named species), Microspora (1), Myxozoa (1), Trematoda (13), Monogenea (3), Cestoda (1), Nematoda (1), Acanthocephala (3), Copepoda (4), and Branchiura (2). For each taxon of parasite, the following information is given: its currently recognized scientific name, any original combination, synonym(s), or other previous identification used for the parasite occurring in ayu; habitat (freshwater, brackish, or marine); site(s) of infection within or on the host; known geographical distribution in Japanese waters; and the published source of each locality record. There has been no record of parasites from a subspecies of ayu, the ryukyu-ayu Plecoglossus altivelis ryukyuensis. The myxozoan Mitraspora plecoglossi Fujita is transferred to the genus Hoferellus (as H. plecoglossi n. comb.), Acanthocephalus opsariichthydis Yamaguti, 1935 is determined to be the nomenclaturally correct spelling and date of that acanthocephalan species, and synonymy of the acanthocephalan Echinorhynchus oblitus Golvan with E. cotti Yamaguti is formally accepted.