Phylogenetic relationships and evolution of the major groups of Siluriformes

In the book chapter we offer a reappraisal of the phylogenetic relationships of the order Siluriformes. Results are based on an original supermatrix ML analysis of sequence data in combination with previously published hypotheses based on both morphology and molecular data. Relationships proposed are summarized in a revised classification of the Siluriformes to family level. The position of Diplomystidae is corroborated as the sister group to all other catfishes, with Loricarioidei as the next sister group to the rest of the order. Other results include a monophyletic group composed of Pangasiidae, Ictaluridae and Cranoglanididae and another including Austroglanididae, Ariidae and Anchariidae. Previously proposed large clades in Africa and Asia are mostly corroborated. A possible narrative biogeographic scenario is described where siluriform continental diversification occurred in tandem with the separation of Gondwana, in close association with the expanding coastal waterways and their occupation of lowland and estuarine environments. All datasets used to generate the trees, including a spreadsheet with GenBank accession numbers, independent alignments of nuclear and mitochondrial genomic markers, concatenated matrices and best-fit partitioning schemes, RAxML log files, and the best ML trees, are available for download at the Zenodo repository (10.5281/zenodo.10535451).