Abstract:
Several studies have demonstrated parasitism by monogenoids in characiform fish in the Neotropics. During studies on the helminth fauna of curimatids from the Tocantins River, specimens of Psectrogasteramazonica Eigenmann & Eigenmann, 1889 were examined and species of Curvianchoratus Hanek, Molnar & Fernando, 1974 were found. Species of the genus are characterized mainly by the complex shape of haptoral anchors with a modified dorsal anchor, composed by two subunits, dorsal-median and dorsal. To date, two species of Curvianchoratus are known to parasitize curimatid fishes: the type species Curvianchoratushexacleidus Hanek, Molnar & Fernando, 1974 and Curvianchoratussingularis (Suriano, 1980). During examination of specimens of P.amazonica collected in the Tocantins River, Embiral, Imperatriz, Maranhão State, Brazil, two new species of Curvianchoratus were found and are described herein. Curvianchoratuspsectrogasterisp. nov. and Curvianchoratusdominguesisp. nov. are characterized by possessing the male copulatory organ formed by a long cirrus and a claw-shaped accessory piece, connected to the base of the male copulatory organ by a ligament. The new species differs from the two known congeneric species mainly by the morphology of the dorsal-median and dorsal subunits of the dorsal anchor. Curvianchoratuspsectrogasterisp. nov. also differs from other species of the genus by the absence of the ventral bar and Curvianchoratusdominguesisp. nov. by the size and shape of the ventral bar. An amendment to the diagnosis of Curvianchoratus is provided to accommodate the new species. The present study increases the number of Curvianchoratus species to four and extends the occurrence of the genus to the Tocantins-Araguaia Basin.
摘要:
几项研究表明,在新热带地区的性状鱼中,单基因组具有寄生作用。在对托坎廷斯河中的猎犬蠕虫动物群的研究中,PsectrogamazonicaEigenmann和Eigenmann的标本,1889年对CurvianchoratusHanek的物种进行了检查,Molnar&Fernando,1974年被发现该属的物种的特征主要在于手锚的复杂形状和改良的背锚,由两个子单元组成,背侧正中和背侧。迄今为止,已知有两种Curvianchoratus寄生于库里马蒂鱼类:类型物种CurvianchoratushexacleidusHanek,Molnar&Fernando,1974年和Curvianchoratussingularis(Suriano,1980).在检查在Tocantins河中收集的P.amazonica标本时,Embiral,Imperatriz,马拉尼昂州,巴西,本文发现并描述了两种新的Curvianchoratus。Curvianchoratuspsectrogasterisp。11月。和Curvianchoratusdominguesissp。11月。其特征是拥有由长卷云和爪形附件形成的雄性交配器官,通过韧带连接到男性交配器官的基部。新物种与两个已知的同类物种的不同之处主要在于背锚的背中和背亚基的形态。Curvianchoratuspsectrogasterisp。11月。与该属的其他物种的不同之处还在于没有腹杆和Curvianchoratusdominguesissp。11月。由腹杆的大小和形状决定。对Curvianchoratus的诊断进行了修改,以适应新物种。本研究将Curvianchoratus物种的数量增加到4种,并将该属的出现扩展到Tocantins-Araguaia盆地。