Museu de Zoologia da Universidade Estadual de Campinas "Adão José Cardoso", Campinas, SP, Brazil.
Laboratorio de Ictiología, Unidad de Ecología y Sistemática (UNESIS), Departamento de Biología, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá, Colombia.
J Fish Biol. 2020 Apr;96(4):868-876. doi: 10.1111/jfb.14267. Epub 2020 Feb 24.
Hemigrammus xaveriellus sp. nov. is described from the upper Río Vaupés basin (Amazon basin), Departamento Guaviare, Colombia. It is distinguished from all congeners by the combination of the following characters: presence of a conspicuous, dark, longitudinal midlateral stripe extending along the body; presence of a conspicuous rounded, horizontally elongated humeral blotch anterior to the beginning of the dark midlateral stripe; seven scale rows between the dorsal fin and lateral line (vs. five to six); and five scale rows between the lateral line and pelvic-fin insertion (vs. three to four). The single mature male of He. xaveriellus possessed a well-developed urogenital papilla, an unusual feature among characids. The presence of an enlarged urogenital papilla in the family is discussed, and comments regarding the putative relationships of the new species are presented.
新物种Hemigrammus xaveriellus 来自上瓦普斯河流域（亚马逊河流域），哥伦比亚瓜维亚雷省。它与所有近缘种的区别在于以下特征的组合：存在一条明显的、深色的、纵向的侧线条纹，沿着身体延伸；存在一个明显的圆形、水平拉长的肩斑，位于深色侧线条纹的开始之前；背鳍和侧线之间有 7 行鳞片（而不是 5 到 6 行）；侧线和臀鳍插入之间有 5 行鳞片（而不是 3 到 4 行）。唯一的成熟雄性 He. xaveriellus 拥有一个发育良好的生殖孔乳头，这是Chars 科中的一个不寻常特征。讨论了家族中存在的扩大的生殖孔乳头，并提出了关于新物种的假定关系的评论。
