01603nas a2200145 4500008004100000022001400041245017700055210006900232260001200301300001400313490000700327520105700334100001801391856004801409 2013 eng d a1029-036200aDifferentiation in morphology and electrical signalling in four species of para- and sympatric Marcusenius (Teleostei: Mormyridae) from Côte d’Ivoire, West Africa0 aDifferentiation in morphology and electrical signalling in four  c03/2013 a105 - 1330 v463 a

Marcusenius Gill, 1862 species were sampled from the Bandama River and the Comoé River in Côte d’Ivoire, West Africa. Marcusenius gracilis sp. nov. was differentiated from M. senegalensis (Steindachner, 1870), Marcusenius ussheri (Günther, 1867) and M. furcidens (Pellegrin, 1920) in electric organ discharges (EOD), and morphologically from all other West African congeners. Principal component analysis showed significant morphological differentiation among the four Ivorian species. Principal component 1 was loaded most strongly by characters affecting swimming power and manoeuvrability. The morphologically most similar pair, M. furcidens and M. gracilis sp. nov., are distinguished by their EOD waveforms and a sexual dimorphism in the anal fin base in the latter not present in the former. M. ussheri is distinguished by a sexual dimorphism in its EOD waveform not observed in the other three species. This system is an opportunity to study how far the fine-tuning of char- acter displacement among syntopic species can go.

1 aKramer, Bernd uhttps://mormyrids.myspecies.info/fr/node/1301677nas a2200157 4500008004100000022001400041245020200055210007100257260001200328300001600340490000700356520107200363100001801435700001801453856004801471 2013 eng d a1464-526200aEast–west differentiation in the Marcusenius macrolepidotus species complex in Southern Africa: the description of a new species for the lower Cunene River, Namibia (Teleostei: Mormyridae)0 aEast–west differentiation in the iMarcusenius macrolepidotusi sp c09/2013 a2327 - 23620 v473 a

This paper critically compares the Southern African bulldog fish species Marcusenius macrolepidotus (Peters, 1852), inhabiting the eastern Lower Zambezi River, and Marcusenius altisambesi Kramer et al., 2007, inhabiting the central Upper Zambezi River, with bulldog fish samples from the western lower Cunene River, a 2600-km range from the Indian Ocean to the Atlantic. The three species or forms are well differentiated in morphology and molecular genetics, and dif- ferentiation is also present in electric organ discharges. Marcusenius altisambesi and the Cunene sample, which we recognize as Marcusenius multisquamatus sp. nov., are closely related and form a sister taxon to M. macrolepidotus. This result is based on the analysis of mitochondrial cytochrome b sequences and genomic Inter-simple-sequence-repeat fingerprinting. Morphological adaptations to life in a torrential escarpment river seem to be present in M. multisquamatus sp. nov. when compared with M. altisambesi, which lives in a reservoir river that periodi- cally floods the savannah.

1 aKramer, Bernd1 aWink, Michael uhttps://mormyrids.myspecies.info/fr/node/11