Franco-Duarte Ricardo, Fernandes Isabel, Gulis Vladislav, Cássio Fernanda, Pascoal Cláudia
CBMA (Centre of Molecular and Environmental Biology), Department of Biology, University of Minho, 4710-057 Braga, Portugal.
Institute of Science and Innovation for Bio-Sustainability (IB-S), University of Minho, 4710-057 Braga, Portugal.
Microorganisms. 2022 Aug 4;10(8):1569. doi: 10.3390/microorganisms10081569.
Aquatic hyphomycetes are key microbial decomposers of allochthonous organic matter in freshwater ecosystems. Although their importance in carbon flow and food webs in streams is widely recognized, there are still gaps in our understanding of their molecular diversity and distribution patterns. Our study utilized the growing database of ITS rDNA barcodes of aquatic hyphomycetes (1252 sequences) and aimed to (i) produce new barcodes for some lesser-known taxa; (ii) clarify the taxonomic placement of some taxa at the class or order level, based on molecular data; and (iii) provide insights into the biogeographical origins of some taxa. This study increased the number of aquatic hyphomycete species with available ITS barcodes from 119 (out of ~300 species described) to 136. Phylogenetically, the 136 species were distributed between 2 phyla, 6 classes, and 10 orders of fungi. Future studies should strive to increase the database of ITS sequences, especially focusing on species with unclear phylogenetic relationships () and with few sequences available. The geographical distribution of species with available ITS sequences included 50 countries from five continents, but 6 countries had more than 20 species associated, showing a bias toward the northern hemisphere, likely due to sampling bias.
水生真菌是淡水生态系统中异源有机物的关键微生物分解者。尽管它们在溪流碳流和食物网中的重要性已得到广泛认可，但我们对其分子多样性和分布模式的理解仍存在差距。我们的研究利用了不断增长的水生真菌ITS rDNA条形码数据库（1252个序列），旨在：（i）为一些鲜为人知的分类群生成新的条形码；（ii）根据分子数据阐明一些分类群在纲或目水平上的分类地位；（iii）深入了解一些分类群的生物地理起源。这项研究使拥有ITS条形码的水生真菌物种数量从119种（约300种已描述物种中的）增加到136种。在系统发育上，这136个物种分布在真菌的2个门、6个纲和10个目中。未来的研究应努力增加ITS序列数据库，尤其要关注系统发育关系不明确且可用序列较少的物种。拥有ITS序列的物种地理分布包括来自五大洲的50个国家，但有6个国家有超过20种相关物种，显示出对北半球的偏向，这可能是由于采样偏差。
