A new small barb (Cyprininae, Smiliogastrini) from the N'sele and Mayi Ndombe rivers in the lower reaches of the middle Congo basin (Democratic Republic of Congo, Central Africa)

Enteromius thespesios (Teleostei: Cyprinidae): a new minnow species with a remarkable sexual dimorphism from the south‐eastern part of the Upper Congo River

“…In E. thespesios , sexual size dimorphism is apparently lacking as the maximum size of the collected males and females is comparable (Table ). Furthermore, no difference is observed in body depth between male and female specimens (Table ), as was the case for E. validus (Table ; Stiassny et al ., , Figure ). The apparent lack of sexual size dimorphism has also been observed in some territorial North American cyprinid species (Pyron, , Figure ) and the resulting absence–presence of sexual size dimorphism for a given species is considered to result from a combination of sexual selection for males better able to mate, guard and defend their territory and natural selection for increased fecundity in females (Parker, ; Pyron, ; Pyron, Pitcher & Jacquemin, ).…”

“…The available information is summarised in Table and concerns observations on four species only; that is, E. candens from the Yangambi area (middle Congo River) as made by Gosse (), on E. candens and E. hulstaerti from Lake Tumba and the Ikela area (middle Congo River) by Matthes () and, more recently, on E. validus from the N′sele and Mayi Ndombe Rivers (lower and middle Congo River, respectively) by Stiassny et al . ().…”

“…This reassignment exclusively concerns species that are not already placed in Barboides Brüning 1929, Barbopsis Di Caporiacco 1926, Caecobarbus Boulenger 1921 and Clypeobarbus Fowler 1936. Although subsequently contested (Schmidt & Bart, ; Stiassny et al ., ; Stiassny & Sakharova, ), this nomenclatural change has been accepted as an onset to the resolution of the taxonomic problem of the genus Barbus (Skelton, , ). Indeed, the pertained use of the informal generic name ‘ Barbus ’ insidiously links the African diploid barbs and the tetraploid Barbus (Skelton, , ) though they belong to two distinct tribes, the Smiliogastrini and Barbini, respectively (see Yang et al ., ).…”