Lehmann A Pablo, Lima FlÁvio C T, Reis Roberto E
Laboratório de Ictiologia, Universidade do Vale do Rio dos Sinos. Av. Unisinos, 950; 93022-000 São Leopoldo, RS, Brazil..
Zootaxa. 2018 Nov 15;4521(4):584-592. doi: 10.11646/zootaxa.4521.4.7.
Parotocinclus yaka is described as a new species of hypoptopomatine cascudinho from tributaries of the Rio Tiquié, tributary to the Rio Uaupés, upper Rio Negro drainage, Amazon basin, Amazonas State, Brazil. The new species is distinguished from its congeners in northeastern and southeastern Brazil by having the cheek canal plate elongated posteriorly on the ventral surface of the head and in contact with the cleithrum. Parotocinclus yaka is diagnosed from the Parotocinclus species of the Amazon, Orinoco and Guianas watersheds by having a conspicuous dark spots smaller than the pupil diameter distributed dorsally and laterally on the head; it is also differentiated from P. polyochrus (Casiquiare, Venezuela), P. longirostris (Rio Amazonas, Brazil), and P. eppleyi (Río Orinoco) by the absence of a Y-shaped light mark dorsally on the head. In addition, the absence of premaxillary and dentary accessory teeth and the presence of a Y-shaped spot on the snout distinguish the new species from P. collinsae (Essequibo River, Guyana), P. halbothi (Rio Trombetas, Brazil and Marowijne River, Suriname) and P. variola (Río Amazonas, Colombia). Parotocinclus yaka also differs from P. amazonensis (lower Amazon basin), P. aripuanensis (lower Amazon basin), P. britskii (Guyana, Suriname, eastern Venezuela, and Amapá State, Brazil), and P. dani (Rio Tapajós basin), by having more numerous oral teeth. The new species described herein is part of the group of small cascudinhos usually associated with marginal or submerged vegetation and submerged logs, of moderate current and clear transparency, found in conserved habitats in streams of the Amazon, Orinoco and Guianas rivers.
雅卡帕氏兵鲶被描述为一种来自巴西亚马孙州亚马孙河流域内格罗河上游乌阿佩斯河的支流蒂基河支流的新物种，属于低眼无齿甲鲶属小型硬骨鲶科鱼类。该新物种与巴西东北部和东南部的同属物种的区别在于，其头部腹面的颊管板向后延长并与匙骨接触。雅卡帕氏兵鲶与亚马孙河、奥里诺科河和圭亚那流域的帕氏兵鲶属物种的区别在于，其头部背面和侧面分布有明显小于瞳孔直径的深色斑点；它还与多斑帕氏兵鲶（委内瑞拉卡西基亚雷河）、长吻帕氏兵鲶（巴西亚马孙河）和埃氏帕氏兵鲶（奥里诺科河）的区别在于，头部背面没有Y形浅色斑纹。此外，无颌前副牙和齿骨副牙，以及吻部有Y形斑点，使该新物种与柯氏帕氏兵鲶（圭亚那埃塞奎博河）、哈尔氏帕氏兵鲶（巴西特龙贝塔斯河和苏里南马罗韦讷河）和花斑帕氏兵鲶（哥伦比亚亚马孙河）区分开来。雅卡帕氏兵鲶与亚马孙帕氏兵鲶（亚马孙河下游流域）、阿里普阿南帕氏兵鲶（亚马孙河下游流域）、布里茨基帕氏兵鲶（圭亚那、苏里南、委内瑞拉东部和巴西阿马帕州）以及达尼帕氏兵鲶（塔帕若斯河流域）的区别还在于，其口腔齿更多。本文描述的新物种属于小型硬骨鲶科鱼类群体，通常与边缘或淹没的植被以及淹没的原木相关联，水流适中，透明度高，见于亚马孙河、奥里诺科河和圭亚那河溪流中的保护栖息地。
