Comprehensive phenotypic phylogenetic analysis supports the monophyly of stromateiform fishes (Teleostei: Percomorphacea)

More than half the ray-finned fishes and about one-quarter of all living vertebrates belong to Percomorphacea. Among its 30 orders, Stromateiformes encompass 77 species in 16 genera and six families. Stromateiform monophyly has never been tested using morphology, and it has been rejected by molecular analyses. This comprehensive revision of Stromateiformes includes all its valid genera of all percomorph families previously aligned with the order. We sampled 207 phenotypic characters in 66 terminal taxa representing 14 orders and 46 acanthopterygian families. This dataset significantly surpasses all previous phenotype-based phylogenies of Stromateiformes, which analysed only a fraction of these characters. Stromateiformes is recovered as monophyletic, supported by eight unequivocal synapomorphies. Amarsipidae is the sister group of all other Stromateiformes (= Stromateoidei). Centrolophidae is paraphyletic, with three of its genera allocated into an early-diverging clade and the other four appearing as successive sister groups to a lineage containing the remaining stromateiforms. All other stromateoid families are monophyletic, with the following cladistic arrangement: (Nomeidae (Stromateidae (Tetragonuridae, Ariommatidae))). Our analysis convincingly refutes recent molecular phylogenetic interpretations that fail to recover a monophyletic Stromateiformes. These findings call into question large-scale conclusions of percomorph relationships and trait evolution based solely on molecular data.