Background

Non-native parasites are often translocated into novel areas together with their natural hosts, but the parasite diversity is frequently lower compared to the host’s native range.

Purpose

This paper provides morphological and molecular characterisation for non-native monogenean parasite Onchocleidus principalis (Ancyrocephalidae) co-introduced with its fish host to Portugal, Europe, including new details on the species’ vaginal morphology and metrics.

Methods

Two host species, the largemouth bass Micropterus salmoides and pumpkinseed sunfish Lepomis gibbosus, were sampled from two reservoirs (Landeira, Coruche) in the Atlantic Sea drainage. Morphometric analysis and sequencing of 28S rDNA were performed.

Results

Presence of O. principalis was confirmed in all individuals of largemouth bass. Accidental findings on pumpkinseed sunfish at both sampling sites represent new host records for this parasite species. The morphometric description of O. principalis showed high similarity to the species in its native range. No intraspecific sequence variation of partial 28S rDNA was observed between specimens from the two sampling sites. Presence of another North-American ancyrocephalid parasite Onchocleidus dispar was confirmed in pumpkinseed sunfish at both sites, and in largemouth bass from the Coruche Reservoir, this representing the first record of O. dispar on largemouth bass in Europe.

Conclusion

Onchocleidus principalis has been confirmed to parasitise both centrarchid fish species introduced to Europe. Compared to other studies, the species collected in Portugal exhibits pronounced vaginal armament.

中文翻译：

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Onchocleidus principalis (Monogenea: Ancyrocephalidae) 与 Centrarchid 鱼共同引入欧洲。

背景

非本地寄生虫通常与其自然宿主一起转移到新的区域，但与宿主的本地范围相比，寄生虫的多样性往往较低。

目的

本文提供了与其鱼类宿主共同引入葡萄牙和欧洲的非本地单基因寄生虫Onchocleidus principalis (Ancyrocephalidae) 的形态学和分子特征，包括有关该物种阴道形态和指标的新细节。

方法

两种寄主物种，即大口黑鲈Micropterus salmoides和南瓜籽翻车鱼Lepomis gibbosus，从大西洋海域的两个水库（​​Landeira、Coruche）取样。进行了 28S rDNA 的形态分析和测序。

结果

在所有大口黑鲈个体中都证实了O. principalis 的存在。在两个采样点对南瓜籽翻车鱼的意外发现代表了该寄生虫物种的新寄主记录。O. principalis的形态学描述显示出与其原生范围内的物种高度相似。在来自两个采样点的样本之间没有观察到部分 28S rDNA 的种内序列变异。在两个地点的南瓜籽翻车鱼和科鲁什水库的大口黑鲈中都证实了另一种北美 ancyrocephalid 寄生虫Onchocleidus dispar 的存在，这是欧洲大口黑鲈上O. dispar的第一个记录。

结论

Onchocleidus principalis已被证实寄生于引入欧洲的两种centrarchid 鱼类。与其他研究相比，在葡萄牙收集的物种表现出明显的阴道武器。