ABSTRACT A new species of the rare genus Trichogenes is reported on the basis of specimens without locality and other associated data. The obvious distinctiveness, taxonomic relevance, and phylogenetic importance of the new taxon justify its description with material at hand. Trichogenes beagle, new species, differs from all congeners by the presence of tricuspidate teeth on its jaws; by the distribution of opercular odontodes along a wide area of the margin of the opercle; by the pale integumentary pigmentation, composed of few scattered small spots on dorsum and flanks, but lacking large spots near the base of the anal fin; and by the absence of differential concentration of dark chromatophores along the base of the dorsal fin. The new species differs further from each of its two congeners, T. longipinnis and T. claviger, by various additional traits of internal and external morphology and pigmentation. Trichogenes beagle seems to be the closest relative of T. claviger, the two species sharing a number of putatively derived traits not present in T. longipinnis, such as the presence of a large anterodorsal clawlike process on the neural arches of the anterior four free vertebrae. The three species now included in Trichogenes share all synapomorphies previously proposed for the genus, thus strongly supporting generic monophyly. The enigmatic disc-shaped orbital bone in T. beagle and congeners is homologous to a topologically equivalent rodlike structure in other trichomycterids. New comparative information corroborates the hypothesis that the bone is a neomorphic structure, here called the barbular bone. Previous proposals of its homology with the antorbital or supraorbital are refuted. Ontogenetic data demonstrate that the anterior element of the infraorbital series in trichomycterids is a fusion between the lacrimal and antorbital, as postulated—but previously poorly demonstrated—for other catfishes. The structure of the opercle in the new species is intermediate between the highly derived morphology in most trichomycterids and the plesiomorphic condition in other loricarioids, helping to understand the evolution of the opercle of trichomycterids. New information on T. claviger is reported on the basis of additional material.

中文翻译：

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Trichogenes 的一个新种 (Siluriformes, Trichomycteridae)，并讨论了 Trichomycterids 和其他 Loricarioids 中前眶骨的同源性

摘要 在没有产地和其他相关数据的标本的基础上，报道了一种新种的稀有毛霉菌属。新分类群的明显独特性、分类学相关性和系统发育重要性证明了其手头材料的描述是合理的。Trichogenes beagle，新物种，与所有同类的区别在于它的下颚上有三尖牙。通过沿鳃盖边缘的大面积分布鳃盖齿；由苍白的外皮色素沉着组成，在背部和侧面由少量分散的小斑点组成，但在臀鳍基部附近没有大斑点；并且由于背鳍基部没有不同浓度的暗色团。新物种与其两个同类中的每一个都进一步不同，T. longipinnis 和 T. claviger，通过内部和外部形态和色素沉着的各种附加特征。Trichogenes beagle 似乎是 T. claviger 的近亲，这两个物种共享许多推定的 T. longipinnis 不存在的特征，例如在前四个游离椎骨的神经弓上存在一个大的前背爪状突起. 现在包括在 Trichogenes 中的三个物种共享先前为该属提出的所有突触，因此强烈支持通用单系。T. beagle 和同类中神秘的圆盘状眶骨与其他毛霉菌中拓扑等效的棒状结构同源。新的比较信息证实了骨骼是一种新形态结构的假设，这里称为倒钩骨。先前关于其与眶前或眶上同源的提议被驳斥。个体发育数据表明，滴虫的眶下系列的前部元件是泪腺和眶前部的融合，正如其他鲶鱼所假设的——但之前没有得到很好的证明。新物种的鳃盖结构介于大多数毛菌纲高度衍生的形态和其他loricarioids 的拟态条件之间，有助于了解毛霉菌纲的进化。在附加材料的基础上报告了关于 T. claviger 的新信息。正如对其他鲶鱼所假设的那样——但之前没有得到很好的证明。新物种的鳃盖结构介于大多数毛菌纲高度衍生的形态和其他loricarioids 的拟态条件之间，有助于了解毛霉菌纲的进化。在附加材料的基础上报告了关于 T. claviger 的新信息。正如对其他鲶鱼所假设的那样——但之前没有得到很好的证明。新物种的鳃盖结构介于大多数毛菌纲高度衍生的形态和其他loricarioids 的拟态条件之间，有助于了解毛霉菌纲的进化。在附加材料的基础上报告了关于 T. claviger 的新信息。