Host-parasite coevolution is one of the main topics of the evolutionary biology of host-parasite associations. The majority of monogeneans parasitizing fish exhibit a high degree of host specificity. As a result, their evolutionary history might be intertwined with that of their fish hosts. The Cichlidae represent a diverse group of secondary freshwater fish with disjunctive distribution. Host-specific dactylogyrid monogeneans commonly parasitize cichlid fish. Their high diversity is associated with the main areas of cichlid distribution, i.e., Neotropical America and Africa. Nevertheless, the parasite fauna of cichlids from Neotropical America is still underexplored. A total of 31 cichlid species were examined for the presence of monogeneans, with 20 of them being parasitized. On these cichlids, 30 monogeneans belonging to the genera Gussevia, Trinidactylus, and Scadicleithrum were identified, 17 of them potentially representing new species for science. Phylogenetic analyses revealed three monophyletic groups of Neotropic cichlid monogeneans. Genus Gussevia was monophyletic, while Sciadicleithrum resulted polyphyletic. Sciedicleithrum from South America and Sciadicleithrum from Mexico represented two divergent lineages. The plesiomorphic Neotropical cichlid host group for dactylogyrid monogeneans was Cichlini, from which the representatives of other Neotropical cichlid tribes were colonised. Cophylogenetic analyses revealed a statistically significant cophylogenetic signal in the investigated host-parasite system, with host switch and duplication representing the main coevolutionary events for monogeneans parasitizing Neotropical cichlids. This scenario is in accordance with previous studies focussed on dactylogyridean monogeneans parasitizing freshwater fish in Europe and Africa.

宿主-寄生虫共同进化是宿主-寄生虫联合进化生物学的主要课题之一。大多数寄生在鱼类上的单基因生物表现出高度的宿主特异性。因此，它们的进化史可能与它们的鱼类宿主的进化史交织在一起。Cichlidae 代表了一个多样化的次生淡水鱼群，具有分离分布。宿主特异性指趾虫通常寄生在丽鱼科鱼身上。它们的高度多样性与慈鲷分布的主要区域有关，即新热带美洲和非洲。尽管如此，来自新热带美洲的丽鱼科鱼的寄生动物群仍未得到充分探索。总共检查了 31 种丽鱼科鱼是否存在单殖子，其中 20 种被寄生。在这些丽鱼科鱼上，有 30 只属于该属的单基因鱼确定了 Gussevia、Trinidactylus和Scadicleithrum，其中 17 个可能代表科学新物种。系统发育分析揭示了新热带慈鲷的三个单系群。Gussevia属是单系的，而Sciadicleithrum属是多系的。来自南美洲的Sciedicleithrum和Sciadicleithrum来自墨西哥的人代表了两个不同的血统。dactylogyrid monogeneanans 的拟形新热带丽鱼科鱼宿主群是 Cichlini，其他新热带丽鱼科鱼部落的代表就是从这个群中定居下来的。共系统发育分析揭示了所研究的宿主-寄生虫系统中具有统计学意义的共系统发育信号，宿主转换和复制代表了寄生新热带丽鱼的单基因生物的主要共同进化事件。这种情况与之前的研究一致，这些研究的重点是指虫寄生在欧洲和非洲的淡水鱼。