Oncoceratium n. gen. is proposed to accommodate Oncoceratium amphidactylum n. gen. n. sp. (Monogenoidea, Gyrodactylidae). Although the proposed genus is monotypic, the differences presented in the diagnosis clearly establish it as distinct from species from other genera, such as Gyrodactylus von Nordmann, 1832 and especially those that occur exclusively in the Neotropical region. The new genus is diagnosed by the presence of a bulbous male copulatory organ, with one row of spinelets of similar sizes and shapes, while the only spine usually found in the gyrodactylids is absent or not differentiated; a haptor with anchors presenting points folded outwards, and superficial and deep roots continuous and indistinguishable; the absence of a deep bar; and hooks in two bilateral clusters of eight hooks. Oncoceratium amphidactylum n. gen. n. sp. is described from the tamboatá fish, Hoplosternum littorale (Hancock) (Callichthyidae), and is characterized by the presence of a pair of horn-shaped anchors with the point turned outwards, a superficial bar shield and absent deep bar, hooks disposed in bilateral lobes, and a MCO with no spine or with a row with large spinelets visible in place of the spine. In addition to the morphological features, distance analysis and Bayesian inference, based on 5.8s and partial ITS2, support placing the new species in a new genus, and not including it in a cluster of species of Gyrodactylus and near to Gyrodactyloides bychowskii Albova, 1948, Ieredactylus rivuli Schelkle et al., 2011 and Laminiscus gussevi (Bychowsky & Polyansky, 1953) Pálsson & Beverely-Burton, 1983.

癌角藻 属 将军 建议容纳Oncoceratium amphidactylum n。将军 名词 sp。（Monogenoidea，Gyrodactylidae）。尽管所提出的属是单一型的，但诊断中呈现的差异清楚地表明它与其他属的物种不同，例如Gyrodactylus von Nordmann, 1832，尤其是那些仅出现在新热带地区的物种。该新属的诊断依据是存在球状雄性交配器官，具有一排大小和形状相似的尖晶石，而通常在轮指科中发现的唯一脊柱不存在或未分化；带有向外折叠点的锚的连体，浅根和深根连续且无法区分；没有深酒吧；和钩子在两个双边集群中，每组八个钩子。Oncoceratium amphidactylum n. 将军 名词 sp。描述自tamboatá鱼Hoplosternum littorale (Hancock) (Callichthyidae)，其特征是存在一对角形锚，尖端向外，有浅杆盾，没有深杆，钩位于双侧裂片中，以及没有书脊或有一排可见大尖晶石代替书脊的 MCO。除了形态特征外，基于5.8s和部分ITS2的距离分析和贝叶斯推理，支持将新物种置于新属中，而不将其包括在Gyrodactylus物种簇中以及靠近Gyrodactyloides bychowskii Albova ， 1948 ，Ieredactylus rivuli Schelkle 等人，2011 年和Laminiscus gussevi（Bychowsky 和 ​​Polyansky，1953 年）Pálsson 和 Beverely-Burton，1983 年。