Takács Péter, Ferincz Árpád, Imecs István, Kovács Balázs, Nagy András Attila, Ihász Katalin, Vitál Zoltán, Csoma Eszter
Balaton Limnological Institute, Centre for Ecological Research, Klebelsberg Kuno str. 3, Tihany, H-8237, Hungary.
Department of Freshwater Fish Ecology, Institute of Aquaculture and Environmental Safety, Hungarian University of Agriculture and Life Sciences, Páter Károly str. 1, Gödöllő, H-2103, Hungary.
BMC Zool. 2021 Mar 6;6(1):3. doi: 10.1186/s40850-021-00069-7.
Phylogenetic studies of widespread European fish species often do not completely cover their entire distribution area, and some areas are often excluded from analyses than others. For example, Carpathian stocks are often omitted from these surveys or are under-represented in the samples. However, this area served as an extra-Mediterranean refugia for many species; therefore, it is assumed that fish stocks here may show special phylogenetic features. For this reason, increased spatial resolution of sampling, namely revealing genetic information from unexamined Carpathian areas within the range of doubtful taxa, may help us better understand their phylogenetic features. To test this hypothesis, a phylogenetic investigation using a partial mtCR sequence data was conducted on 56 stream-dwelling freshwater fish (Gobio spp.) individuals collected from 11 rivers of the data-deficient Southeastern Carpathian area. Moreover, we revieved the available phylogenetic data of Middle-Danubian stream-dwelling gudgeon lineages to delineate their distribution in the area.
Seven out of the nine detected haplotypes were newly described, suggesting the studied area hosts distinct and diverse Gobio stocks. Two valid species (G. obtusirostris, G. gobio), and a haplogroup with doubtful phylogenetic position" G. sp. 1" were detected in the area, showing a specific spatial distribution pattern. The distribution of the detected lineages in the Middle-Danubian area correspond with recent and paleo hydrogeographic features, at the same time mainly on their bordering areas show considerable overlap.
Despite the relatively limited geographic range of the study, our results provide important information which contributes to a better understanding of the phylogenetic, taxonomic and distribution features of Central European gudgeons. The genetically confirmed distribution data of the indicated lineages corresponds well with the recent and near-recent hydrogeographic features of the area, and assumes several hybrid zones in the Carpathian Basin. Additionally, the results show that the middle and lower Danubian watershed cannot be excluded from the range of G. gobio. Moreover, the" G. sp. 1", is slightly differentiated but phylogenetically distinct entity, and is the only Gobio taxa thus far detected in the middle and lower Tisza-basin. However, further investigations are necessary to clarify the taxonomic position of this group.
对分布广泛的欧洲鱼类物种进行的系统发育研究往往没有完全覆盖其整个分布区域，而且某些区域比其他区域更常被排除在分析之外。例如，喀尔巴阡山脉的种群在这些调查中常常被遗漏，或者在样本中的代表性不足。然而，该地区曾是许多物种的地中海以外避难所；因此，人们认为这里的鱼类种群可能具有特殊的系统发育特征。出于这个原因，提高采样的空间分辨率，即在可疑分类群范围内从未经研究的喀尔巴阡山脉地区揭示遗传信息，可能有助于我们更好地了解它们的系统发育特征。为了验证这一假设，我们对从数据缺乏的东南喀尔巴阡山脉地区的11条河流中采集的56条栖息于溪流的淡水鱼（戈比属）个体进行了基于部分线粒体控制区（mtCR）序列数据的系统发育调查。此外，我们回顾了多瑙河中游栖息于溪流的 gudgeon 谱系的现有系统发育数据，以描绘它们在该地区的分布。
九个检测到的单倍型中有七个是新描述的，这表明研究区域拥有独特且多样的戈比种群。在该地区检测到两个有效物种（钝吻戈比、戈比）以及一个系统发育位置存疑的单倍型类群“戈比 1 号”，呈现出特定的空间分布模式。多瑙河中游地区检测到的谱系分布与近期和古水文地理特征相符，同时主要在其边界区域显示出相当大的重叠。
尽管研究的地理范围相对有限，但我们的结果提供了重要信息，有助于更好地理解中欧 gudgeon 的系统发育、分类和分布特征。所示谱系的经基因确认的分布数据与该地区近期和近近期的水文地理特征相符，并假定喀尔巴阡盆地存在几个杂交区。此外，结果表明多瑙河中下游流域不能被排除在戈比的分布范围之外。此外，“戈比 1 号”是一个略有分化但在系统发育上独特的实体，是迄今为止在蒂萨河中下游流域检测到的唯一戈比分类群。然而，需要进一步调查以澄清该类群的分类地位。
