This study aims to investigate relationships between species traits and publication date in the weakly electric osteoglossiform Mormyroidea (African knifefish and elephantfishes) and the ostariophysan Gymnotiformes (Neotropical knifefishes). It is investigated whether body size and geographic distribution area are correlated with publication date and whether extinction risk differs between both phylogenetically distant and geographically isolated clades. Statistical modelling indicates that the number of new species described annually is stable in mormyroids and clearly increasing in gymnotiforms. Best-fitting generalised linear models (GLM) indicate that the newly discovered species are more often of small-bodied, predominantly narrowly distributed and more likely to be threatened with extinction. These characteristics are more pronounced in mormyroids when compared with gymnotiforms, suggesting that some African electric fishes may live an ephemeral existence after formal description. Despite taxonomic work has been more intense in the Neotropics than in Africa in the recent decades, there is evidence that the African continent represents the next frontier of species descriptions. Taxonomic studies are fundamental for the understanding of richness and distribution and hence extinction risk assessment and conservation, of these remarkable convergent fish clades.
Keywords: conservation; publication date; species discovery; taxonomy; traits; weakly electric fishes.
© 2019 The Fisheries Society of the British Isles.