Soares R X, Cioffi M B, Bertollo L A C, Borges A T, Costa G W W F, Molina W F
Departamento de Biologia Celular e Genética, Centro de Biociências, Universidade Federal do Rio Grande do Norte, Campus Universitário, , Brasil.
Departamento de Genética e Evolução, , , Brasil.
Genet Mol Res. 2017 Apr 20;16(2):gmr-16-02-gmr.16029644. doi: 10.4238/gmr16029644.
Sphyraena (barracudas) represents the only genus of the Sphyraenidae family and includes 27 species distributed into the tropical and subtropical oceanic regions. These pelagic predators can reach large sizes and, thus, attracting significant interest from commercial and sport fishing. Evolutionary data for this fish group, as well its chromosomal patterns, are very incipient. In the present study, the species Sphyraena guachancho, S. barracuda, and S. picudilla were analyzed under conventional (Giemsa staining, C-banding, and Ag-NOR) and molecular (CMA banding, and in situ hybridization with 18S rDNA, 5S rDNA, and telomeric probes) cytogenetic methods. The karyotypic patterns contrast with the current phylogenetic relationships proposed for this group, showing by themselves to be distinct among closely related species, and similar among less related ones. This indicates homoplasic characteristics, with similar karyotype patterns originating at least twice, independently. Although still cytogenetically poor investigated, our data were enough to put in evidence a variety of ancient conserved traits and evolutionary novelties for the Sphyraena genus. In this sense, it is fundamental that a larger number of Sphyraenidae species, as well as of other phylogenetically related families, be also investigated. This will solidify the knowledge of their karyotypic patterns, and the evolutionary path followed by the species of this particular fish family.
魣属（梭鱼）是魣科唯一的属，包含27个物种，分布于热带和亚热带海洋区域。这些远洋食肉鱼类体型较大，因此吸引了商业捕鱼和休闲捕鱼的极大兴趣。关于这个鱼类群体的进化数据及其染色体模式，目前还非常有限。在本研究中，采用传统（吉姆萨染色、C带染色和银染核仁组织区）和分子（CMA带染色以及用18S rDNA、5S rDNA和端粒探针进行原位杂交）细胞遗传学方法，对瓜氏魣、大魣和小魣进行了分析。核型模式与目前为该群体提出的系统发育关系形成对比，显示出在亲缘关系密切的物种之间核型模式各不相同，而在亲缘关系较远的物种之间则相似。这表明存在同塑性特征，相似的核型模式至少独立起源了两次。尽管在细胞遗传学方面的研究仍然较少，但我们的数据足以证明魣属具有多种古老的保守特征和进化新特征。从这个意义上说，对更多的魣科物种以及其他系统发育相关的科进行研究至关重要。这将巩固我们对它们核型模式以及这个特定鱼类科的物种所遵循的进化路径的认识。
