Instituto de Biodiversidade e Sustentabilidade (NUPEM), Universidade Federal do Rio de Janeiro (UFRJ), Macaé, Rio de Janeiro, Brazil.
Programa de Pós-Graduação em Ciências Ambientais e Conservação (PPG-CiAC), Instituto de Biodiversidade e Sustentabilidade (NUPEM), Universidade Federal do Rio de Janeiro (UFRJ), Macaé, Rio de Janeiro, Brazil.
PeerJ. 2024 Jul 25;12:e17791. doi: 10.7717/peerj.17791. eCollection 2024.
Knowledge on species composition is the first step necessary for the proper conservation and management of biological resources and ecologically relevant species. High species diversity and a lack of diagnostic characters for some groups can impose difficulties for taxonomic identification through traditional methodologies, and ichthyoplankton (fish larvae and eggs) are a good example of such a scenario. With more than 35.000 valid species of fishes worldwide and overall similar anatomies in early developmental stages in closely related groups, fish larvae are often hard to be identified at the species or even more encompassing taxonomic levels. To overcome this situation, molecular techniques have been applied, with different markers tested over the years. Cytochrome c oxidase I (COI) is the most commonly used marker and now has the broadest public reference libraries, providing consistent results for species identification in different metazoan studies. Here we sequenced the mitochondrial COI-5P fragment of 89 fish larvae collected in the Campos Basin, coastal southeastern Brazil, and compared these sequences with references deposited in public databases to obtain taxonomic identifications. Most specimens identified are species of the Blenniiformes, with and the most frequently identified genera. included two species ( and ), while included three species (, and ). Anatomy of these molecularly identified specimens were then analyzed with the intention of finding anatomical characters that might be diagnostically informative amongst the early development stage (pre-flexion) larvae. Ventral pigmentation patterns are proposed as useful markers to identify species. However, additional specimens are needed to confirm if the character holds stability through the geographic distribution of the species.
物种组成的知识是正确保护和管理生物资源和生态相关物种的必要第一步。高物种多样性和一些群体缺乏诊断特征会给通过传统方法进行分类鉴定带来困难，而仔鱼（鱼类幼虫和卵）就是这种情况的一个很好的例子。全世界鱼类的有效物种超过 35000 种，在亲缘关系密切的群体中，早期发育阶段的总体解剖结构相似，鱼类幼虫通常很难在物种甚至更广泛的分类水平上进行鉴定。为了克服这种情况，已经应用了分子技术，多年来测试了不同的标记物。细胞色素 c 氧化酶 I（COI）是最常用的标记物，现在具有最广泛的公共参考文库，为不同后生动物研究中的物种鉴定提供了一致的结果。在这里，我们对在巴西东南沿海坎波斯盆地采集的 89 条仔鱼的线粒体 COI-5P 片段进行了测序，并将这些序列与公共数据库中保存的参考序列进行比较，以获得分类鉴定。大多数鉴定的标本是鳚形目鱼类，其中 和 是最常见的属。 包括两个物种（ 和 ），而 包括三个物种（ 、 和 ）。然后分析了这些通过分子鉴定的标本的解剖结构，目的是找到在早期发育阶段（弯曲前）幼虫中可能具有诊断意义的解剖特征。腹面色素模式被提议作为识别 物种的有用标记。然而，需要更多的标本来确认该特征是否在物种的地理分布中保持稳定。
