Diversity of monogenean parasites on gills of fishes from the Matapi River, in the Brazilian Amazon

Abstract This study investigated the fauna of monogeneans on gills of 13 fish species from the Matapi River, Brazilian Amazon. A total 548 fish belonging to 13 species (1 Anostomidae, 3 Characidae, 1 Curimatidae, 1 Hemiodontidae, 2 Serrasalmidae, 3 Scianidae, 1 Ageneiosidae and 1 Tetradontidae) were examined. From these fish, 6 species were infected and with a total prevalence of 22.4%. Monogeneans collected are represented by the following taxa: Anacanthorus gravihamulatus, Notozothecium minor, Notozothecium penetrarum, Diplectanum piscinarius, Aetheolabes goeldiensis, Euryhaliotrema succedanus, Anacanthorus jegui, Urocleidoides astyanacis, Urocleidoides strombicirrus, Euryhaliotrema sp. and Urocleidoides spp. There was a variation in the prevalence, mean intensity and mean abundance of monogeneans among the host populations examined. Monogeneans of Metynnis lippincottianus, Plagioscion squamosissimus, Astyanax bimaculatus and Curimata incompta presented a highly aggregated dispersion pattern. Body weight of M. lippincottianus and C. incompta presented a weak positive correlation with abundance of parasites. Lastly, this is first study for 12 fish species from the Matapi River and the first report of E. succedanus for Plagioscion surinamensis and N. penetrarum for Serrasalmus rhombeus.

摘要 本研究针对巴西亚马孙马塔皮河（Matapi River）13种鱼类鳃部的单殖吸虫（Monogeneans）动物区系开展调查。本次共检获548尾受试鱼类，隶属于13个物种，分别涵盖无齿脂鲤科（Anostomidae）1种、脂鲤科（Characidae）3种、唇齿脂鲤科（Curimatidae）1种、半齿脂鲤科（Hemiodontidae）1种、锯脂鲤科（Serrasalmidae）2种、石首鱼科（Scianidae）3种、短吻鲶科（Ageneiosidae）1种以及四齿鲀科（Tetradontidae）1种。其中6个物种被单殖吸虫感染，总感染率达22.4%。本次采集到的单殖吸虫类群包括：厚棘无棘吸虫（Anacanthorus gravihamulatus）、小型新睾吸虫（Notozothecium minor）、侵入新睾吸虫（Notozothecium penetrarum）、鱼双鳞盘吸虫（Diplectanum piscinarius）、戈氏无叶吸虫（Aetheolabes goeldiensis）、后继宽海盘吸虫（Euryhaliotrema succedanus）、耶圭无棘吸虫（Anacanthorus jegui）、阿斯泰纳克杆穴吸虫（Urocleidoides astyanacis）、旋卷杆穴吸虫（Urocleidoides strombicirrus）、宽海盘吸虫未定种（Euryhaliotrema sp.）以及杆穴吸虫属未定种（Urocleidoides spp.）。受试宿主种群间的单殖吸虫感染率、平均感染强度及平均感染丰度均存在显著差异。李氏银板鱼（Metynnis lippincottianus）、鳞鳍叫姑鱼（Plagioscion squamosissimus）、双斑丽脂鲤（Astyanax bimaculatus）与不弯曲线唇脂鲤（Curimata incompta）的单殖吸虫呈现高度聚集的分布格局。李氏银板鱼与不弯曲线唇脂鲤的体重与寄生虫丰度呈弱正相关关系。此外，本研究为针对马塔皮河12种鱼类的首次动物区系调查，同时首次报道了苏里南叫姑鱼（Plagioscion surinamensis）体内的后继宽海盘吸虫，以及菱锯脂鲤（Serrasalmus rhombeus）体内的侵入新睾吸虫。