title: Taxonomic challenges in freshwater fishes: a mismatch between morphology and DNA barcoding in fish of the north-eastern part of the Congo basin.
abstract: This study evaluates the utility of DNA barcoding to traditional morphology-based species identifications for the fish fauna of the north-eastern Congo basin. We compared DNA sequences (COI) of 821 samples from 206 morphologically identified species. Best match, best close match and all species barcoding analyses resulted in a rather low identification success of 87.5%, 84.5% and 64.1%, respectively. The ratio 'nearest-neighbour distance/maximum intraspecific divergence' was lower than 1 for 26.1% of the samples, indicating possible taxonomic problems. In ten genera, belonging to six families, the number of species inferred from mtDNA data exceeded the number of species identified using morphological features; and in four cases indications of possible synonymy were detected. Finally, the DNA barcodes confirmed previously known identification problems within certain genera of the Clariidae, Cyprinidae and Mormyridae. Our results underscore the large number of taxonomic problems lingering in the taxonomy of the fish fauna of the Congo basin and illustrate why DNA barcodes will contribute to future efforts to compile a reliable taxonomic inventory of the Congo basin fish fauna. Therefore, the obtained barcodes were deposited in the reference barcode library of the Barcode of Life Initiative.
authors.affiliation: Department of Biology, Laboratory of Biodiversity and Evolutionary Genomics, KU Leuven, Charles Deberiotstraat 32, 3000, Leuven, Belgium.|Section Vertebrates, Ichthyology, Royal Museum for Central Africa, Leuvensesteenweg 13, 3080, Tervuren, Belgium.
authors.forename: Eva
authors.initials: E
authors.lastname: Decru
authors.affiliation: Department of Biology, Laboratory of Biodiversity and Evolutionary Genomics, KU Leuven, Charles Deberiotstraat 32, 3000, Leuven, Belgium.|Section Vertebrates, Ichthyology, Royal Museum for Central Africa, Leuvensesteenweg 13, 3080, Tervuren, Belgium.
authors.forename: Tuur
authors.initials: T
authors.lastname: Moelants
authors.affiliation: OD Taxonomy and Phylogeny, Royal Belgian Institute for Natural Sciences, Vautierstraat 29, 1000, Brussels, Belgium.
authors.forename: Koen
authors.initials: K
authors.lastname: De Gelas
authors.affiliation: Department of Biology, Laboratory of Biodiversity and Evolutionary Genomics, KU Leuven, Charles Deberiotstraat 32, 3000, Leuven, Belgium.|Section Vertebrates, Ichthyology, Royal Museum for Central Africa, Leuvensesteenweg 13, 3080, Tervuren, Belgium.
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Vreven
authors.affiliation: OD Taxonomy and Phylogeny, Royal Belgian Institute for Natural Sciences, Vautierstraat 29, 1000, Brussels, Belgium.|Biology Department, Evolutionary Ecology Group, University of Antwerp, Groenenborgerlaan 171, 2020, Antwerpen, Belgium.
authors.forename: Erik
authors.initials: E
authors.lastname: Verheyen
authors.affiliation: Department of Biology, Laboratory of Biodiversity and Evolutionary Genomics, KU Leuven, Charles Deberiotstraat 32, 3000, Leuven, Belgium.|Section Vertebrates, Ichthyology, Royal Museum for Central Africa, Leuvensesteenweg 13, 3080, Tervuren, Belgium.
authors.forename: Jos
authors.initials: J
authors.lastname: Snoeks
mesh_terms: D000818:Animals; D044822:Biodiversity; D002397:Catfishes / Q000145:classification / Q000235:genetics; D003223:Congo; D003530:Cyprinidae / Q000033:anatomy & histology / Q000145:classification / Q000235:genetics; D058893:DNA Barcoding, Taxonomic / Q000379:methods*; D003576:Electron Transport Complex IV / Q000235:genetics; D029941:Fish Proteins / Q000235:genetics; D005399:Fishes / Q000033:anatomy & histology / Q000145:classification* / Q000235:genetics; D010802:Phylogeny
chemical_list: D029941:Fish Proteins; D003576:Electron Transport Complex IV
keywords: Congo Basin; biodiversity; cytochrome c oxidase subunit 1; taxonomic diversity detection