Héritier Laurent, Verneau Olivier, Smith Kevin G, Coetzer Carina, Du Preez Louis H
University of Perpignan Via Domitia, Centre de Formation et de Recherche sur les Environnements Méditerranéens, UMR 5110, F-66860 Perpignan, France; CNRS, Centre de Formation et de Recherche sur les Environnements Méditerranéens, UMR 5110, F-66860 Perpignan, France; Unit for Environmental Sciences and Management, North-West University, Potchefstroom 2520, South Africa.
Davidson College, Biology Department, Box 7118, Davidson, NC 28035, USA.
Parasitol Int. 2018 Feb;67(1):38-46. doi: 10.1016/j.parint.2017.03.002. Epub 2017 Mar 20.
Polystomes are monogenean parasites that infest mainly semi aquatic vertebrates, such as amphibians and chelonians. Owing to the lack of discriminative morphological characters and because polystomes are considered to be strictly host- and site-specific, host identity is often used as an additional character for parasite identification. Recent genetic studies, however, showed that polystomes infecting freshwater turtles in outdoor turtle enclosures and natural environments, were not strictly host-specific. Therefore, we proposed a new procedure for turtle polystome taxonomy based on the combination of Cytochrome c Oxydase I sequences and two discriminant morphological characters, namely the number of genital spines and the testis shape. We tested the validity of this procedure with Polystomoides oris, which was collected from the pharyngeal cavity of the American painted turtle Chrysemys picta and two undescribed species, both collected from the pharyngeal cavity of the American slider Trachemys scripta and two other European turtles, namely the European pond turtle Emys orbicularis and the Mediterranean turtle Mauremys leprosa. A Principal Component Analysis based on both morphological characters allowed the separation of all specimens in three morphological groups, which matched well with the molecular data. As a result, we describe two new polystome species, i.e., Polystomoides soredensis n. sp. and Polystomoides scriptanus n. sp.
多盘虫是单殖吸虫类寄生虫，主要寄生于半水生脊椎动物，如两栖动物和龟类。由于缺乏可区分的形态特征，且多盘虫被认为具有严格的宿主和寄生部位特异性，宿主身份常被用作寄生虫鉴定的附加特征。然而，最近的遗传学研究表明，感染室外龟池和自然环境中淡水龟的多盘虫并非严格的宿主特异性。因此，我们基于细胞色素c氧化酶I序列以及两个判别性形态特征（即生殖棘数量和睾丸形状）的组合，提出了一种新的龟多盘虫分类方法。我们用从美国彩龟（Chrysemys picta）咽腔采集的口多盘虫（Polystomoides oris）以及从美国滑龟（Trachemys scripta）咽腔采集的两个未描述物种，还有另外两种欧洲龟，即欧洲池龟（Emys orbicularis）和地中海龟（Mauremys leprosa），对该方法的有效性进行了测试。基于这两个形态特征的主成分分析将所有标本分为三个形态组，这与分子数据匹配良好。结果，我们描述了两个新的多盘虫物种，即索雷登斯多盘虫（Polystomoides soredensis n. sp.）和斯克里普塔多盘虫（Polystomoides scriptanus n. sp.）。
