Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, Ceske Budejovice, Czech Republic.
Department of Invertebrates, Natural History Museum of Geneva, Geneva, Switzerland.
Folia Parasitol (Praha). 2024 Oct 22;71:2024.019. doi: 10.14411/fp.2024.019.
Tapeworms of the genus Proteocephalus Weinland, 1858 (Cestoda: Proteocephalidae) are common and widespread intestinal parasites of whitefish (Coregonus spp., Salmonidae: Coregoninae). Previous taxonomic studies, based solely on morphology and inconsistently fixed specimens, concluded that all salmoniform fish, including whitefish, are parasitised by a single euryxenous and highly polymorphic species, Proteocephalus longicollis (Zeder, 1800). However, recent molecular phylogenetic analyses have revealed the existence of several species specific to individual genera or even species of salmoniform fish. In this study, Proteocephalus fallax La Rue, 1911 is redescribed based on newly collected and genetically characterised specimens from several Coregonus species in Switzerland, the type locality of the species, and in Norway. This cestode was previously synonymised with P. exiguus La Rue, 1911, a parasite of whitefish in North America, but the two species are not closely related. Proteocephalus fallax differs from P. exiguus in its larger body size, wider proglottids, shorter cirrus sac and broader scolex. In addition, the other Proteocephalus species described in whitefish are briefly discussed, with comments on their validity, host range and distribution.
绦虫属的 Proteocephalus Weinland，1858 年（Cestoda：Proteocephalidae）是白鲑科（Coregonidae：Coregoninae）中常见且广泛分布的肠道寄生虫。以前的分类学研究仅基于形态学和不一致固定的标本，得出的结论是，所有的鲑形目鱼类，包括白鲑，都被一种单一的、广生态位和高度多态的物种 Proteocephalus longicollis (Zeder, 1800)寄生。然而，最近的分子系统发育分析揭示了存在几种特定于个别属甚至鲑形目鱼类种的物种。在这项研究中，基于从瑞士、该物种的模式产地和挪威的几种白鲑科物种中收集到的新的遗传特征标本，重新描述了 Proteocephalus fallax La Rue，1911。这种绦虫以前曾被归为 P. exiguus La Rue，1911 的同物异名，后者是北美的白鲑寄生虫，但这两个物种并没有密切相关。与 P. exiguus 相比，Proteocephalus fallax 的体型更大，节片更宽，环槽囊更短，头节更宽。此外，还简要讨论了在白鲑中描述的其他 Proteocephalus 物种，包括它们的有效性、宿主范围和分布。
