Towards a revision of the large-sized Distichodus Müller & Troschel, 1844 (Characiformes: Distichodontidae) species from the Congo basin
MetadataShow full item record
Currently 14 valid Distichodus species are known from the Congo basin, eight of which belong to the group of large-sized species (max. size ≥ 310 mm TL). Within this group, three species are easily identified, i.e. D. maculatus by its round, blackish spots all over the body, D. lusosso by its terminal mouth and distinctively prolonged snout and D. sexfasciatus by its strongly compressed snout and orange-reddish body coloration, the latter only shared with D. lusosso. However, identification of the five remaining species is more problematic and has been subject to numerous misidentifications in the past. Species included within this group are D. antonii, D. atroventralis, D. fasciolatus, D. langi and D. mossambicus. Eight meristics and 28 measurements were taken on a total of 126 specimens. Results of Principal Component Analyses and Mann Whitney U-tests confirmed D. antonii, D. fasciolatus and D. langi to be valid species, even though the latter has for long been considered a possible junior synonym of D. antonii. Distichodus antonii can be distinguished from the other two species by its terminal mouth and larger internasal distance, while D. fasciolatus can be separated from D. langi by its lower dorsal, pectoral and pelvic fin ray counts. Reports of D. mossambicus from the Congo basin are found to be based on misidentifications. Results show these Congo basin specimens to be more similar to D. atroventralis, and were put together in the D. atroventralis complex. This complex is currently under study, but preliminary results already revealed it to contain two new species, one from the Kasai basin and another from Inga, Lower Congo.
CitationMoelants, T.; Mbadu Zebe, V.; Snoeks, J.; Vreven, E. (2013). Towards a revision of the large-sized Distichodus Müller & Troschel, 1844 (Characiformes: Distichodontidae) species from the Congo basin. , Fifth International Conference of the Pan African Fish and Fisheries Association (PAFFA5),