Instituto de Biociências, Setor de Parasitologia, Universidade Estadual Paulista "Júlio de Mesquita Filho" (UNESP), Rua Prof. Dr. Antônio Celso Wagner Zanin, s/n, Botucatu, São Paulo, 18616-689, Brazil.
Syst Parasitol. 2024 Apr 18;101(3):30. doi: 10.1007/s11230-024-10158-z.
Neotropical fish amphistomes represent a highly diverse group within the Paramphistomoidea, with wide distribution across major South American hydrological drainages. However, the limited molecular characterization of these taxa has impeded a comprehensive assessment of their evolutionary relationships and the systematic relevance of morphological features in classification schemes. Our study, based on the critical evaluation of the type material of both nominal species of Zonocotyle (type genus of the monotypic Zonocotylidae), and newly collected specimens of Zonocotyle bicaecata from Steindachnerina insculpta (Curimatidae) in the Upper Paraná River basin, Brazil, presents a morphological reappraisal of Z. bicaecata and provides molecular data (28S rDNA, ITS1-5.8S-ITS2 region, and COI mtDNA) to assess its phylogenetic relationships. Our phylogenetic analyses confirm this species belongs to the Paramphistomoidea. The most comprehensive analyses (based on 28S and COI) further indicate a close relationship with other fish amphistomes from the Neotropical region. Additionally, we emphasized the necessity for a new classification within Paramphistomoidea and briefly discussed the host range of Zonocotyle among curimatid fish hosts.
新热带鱼复殖吸虫是 Paramphistomoidea 中一个高度多样化的群体，广泛分布于南美洲主要的水文流域。然而，这些分类群的分子特征描述有限，阻碍了对其进化关系和分类方案中形态特征的系统相关性的全面评估。我们的研究基于对 Zonocotyle（Zonocotylidae 的单种属）的两个种本名的模式标本的批判性评估，以及在巴西上巴拉那河流域从 Steindachnerina insculpta（Curimatidae）中采集的新的 Zonocotyle bicaecata 标本，对 Z. bicaecata 进行了形态再评价，并提供了分子数据（28S rDNA、ITS1-5.8S-ITS2 区和 COI mtDNA）来评估其系统发育关系。我们的系统发育分析证实该物种属于 Paramphistomoidea。最全面的分析（基于 28S 和 COI）进一步表明，它与来自新热带地区的其他鱼类复殖吸虫密切相关。此外，我们强调了在 Paramphistomoidea 内进行新分类的必要性，并简要讨论了 Zonocotyle 在 Curimatidae 鱼类宿主中的宿主范围。
