Lujan Nathan K, Cramer Christian A, Covain Raphael, Fisch-Muller Sonia, López-Fernández Hernán
Department of Biological Sciences, University of Toronto Scarborough, Toronto, Ontario M1C 1A4, Canada; Department of Natural History, Royal Ontario Museum, 100 Queen's Park, Toronto, Ontario M5S 2C6, Canada; Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Ontario M5S 3B2, Canada.
Laboratório de Ictiologia e Pesca, Departamento de Biologia, Universidade Federal de Rondônia, BR 364, Km 9.5, CEP: 76801-059 Porto Velho, Brazil.
Mol Phylogenet Evol. 2017 Apr;109:321-336. doi: 10.1016/j.ympev.2016.12.040. Epub 2017 Jan 5.
Approximately two-dozen species in three genera of the Neotropical suckermouth armored catfish family Loricariidae are the only described fishes known to specialize on diets consisting largely of wood. We conducted a molecular phylogenetic analysis of 10 described species and 14 undescribed species or morphotypes assigned to the wood-eating catfish genus Panaqolus, and four described species and three undescribed species or morphotypes assigned to the distantly related wood-eating catfish genus Panaque. Our analyses included individuals and species from both genera that are broadly distributed throughout tropical South America east of the Andes Mountains and 13 additional genera hypothesized to have also descended from the most recent common ancestor of Panaqolus and Panaque. Bayesian and maximum likelihood analyses of two mitochondrial and three nuclear loci totaling 4293bp confirmed respective monophyly of Panaqolus, exclusive of the putative congener 'Panaqolus' koko, and Panaque. Members of Panaqolus sensu stricto were distributed across three strongly monophyletic clades: a clade of 10 generally darkly colored, lyretail species distributed across western headwaters of the Amazon Basin, a clade of three irregularly and narrowly banded species from the western Orinoco Basin, and a clade of 11 generally brown, broadly banded species that are widely distributed throughout the Amazon Basin. We erect new subgenera for each of these clades and a new genus for the morphologically, biogeographically and ecologically distinct species 'Panaqolus' koko. Our finding that perhaps half of the species-level diversity in the widespread genus Panaqolus remains undescribed illustrates the extent to which total taxonomic diversity of small and philopatric, yet apparently widely distributed, Amazonian fishes may remain underestimated. Ranges for two Panaqolus subgenera and the genus Panaque overlap with the wood-eating genus Cochliodon in central Andean tributaries of the upper Amazon Basin, which appear to be a global epicenter of wood-eating catfish diversity.
新热带吸口甲鲶科（Loricariidae）三个属中的大约二十多种已知鱼类是唯一专门以主要由木材组成的食物为食的已描述鱼类。我们对10个已描述物种以及14个未描述物种或形态型进行了分子系统发育分析，这些物种或形态型被归入食木鲶属Panaqolus，还对4个已描述物种以及3个未描述物种或形态型进行了分析，这些被归入亲缘关系较远的食木鲶属Panaque。我们的分析包括来自这两个属的个体和物种，它们广泛分布于安第斯山脉以东的热带南美洲，以及另外13个被假设也起源于Panaqolus和Panaque最近共同祖先的属。对两个线粒体和三个核基因座共4293bp进行的贝叶斯分析和最大似然分析证实了Panaqolus（不包括假定的同属物种“Panaqolus”koko）和Panaque各自的单系性。狭义的Panaqolus成员分布在三个高度单系的分支中：一个分支包含10种通常颜色较深的琴尾物种，分布在亚马逊河流域西部的源头；一个分支包含3种来自奥里诺科河流域西部的不规则且窄带状物种；还有一个分支包含11种通常为棕色、宽带状的物种，广泛分布于整个亚马逊河流域。我们为这些分支中的每一个建立了新的亚属，并为形态、生物地理和生态上独特的物种“Panaqolus”koko建立了一个新属。我们的发现表明，广泛分布的Panaqolus属中可能有一半的物种水平多样性仍未被描述，这说明了小型且恋巢但显然分布广泛的亚马逊鱼类的总分类多样性可能仍被低估的程度。两个Panaqolus亚属和Panaque属的分布范围与亚马逊河上游安第斯山脉中部支流中的食木属Cochliodon重叠，这里似乎是食木鲶鱼多样性的全球中心。
