02153nas a2200169 4500008004100000022001400041245015600055210006900211260001600280300000800296490000900304520155700313100001801870700002401888700001401912856005701926 2016 eng d a1175-532600aElectric organ discharges of South African Marcusenius species (Teleostei: Mormyridae) and their effectiveness as indicators of local species diversity0 aElectric organ discharges of South African Marcusenius species T cMay-11-2018 a3670 v42003 a

Recent morphological and genetic studies have revealed two new species of snoutfish in South Africa, Marcusenius caudisquamatus and M. krameri, which had been confused with M. pongolensis, the South African bulldog fish. All known mormyriform fish are nocturnal and emit electric organ discharges (EODs) for communication that are characteristic for their species. This paper examines whether or not the EODs of these three closely-related South African species can be differentiated from each other. An EOD pulse of a bulldog fish consists of a head-positive phase P, followed by a head-negative phase N of short duration. We measured and compared six variables of the EOD pulse waveform for South African samples for the three species from different locations using MANOVA, ANOVA and Discriminant Analysis, with M. devosi from Kenya as an outgroup. The EOD waveforms, normalized to the same P-phase amplitude, varied significantly from each other in four variables, most strongly in the amplitude of the N phase and the duration of the P phase. In two species, M. devosi and M. krameri, there was no evidence of difference between sexes, in contrast to M. pongolensis and M. caudisquamatus whose male pulses were of longer duration. M. devosi and M. krameri were statistically significantly independent of each other and of any other group studied. By contrast, the M. pongolensis specimens from different locations showed a high degree of variability amongst each other, including significant separation, and overlap with M. caudisquamatus.

1 aKramer, Bernd1 aMaake, Pholoshi, A.1 aGon, Ofer uhttp://biotaxa.org/Zootaxa/issue/view/zootaxa.4200.302046nas a2200229 4500008004100000022001400041245010400055210006900159260001600228300001100244520130700255653001201562653003001574653002801604653001501632653001901647653001501666100001801681700002901699700001801728856007001746 2016 eng d a1608-591400aMarcusenius desertus sp. nov. (Teleostei: Mormyridae), a mormyrid fish from the Namib desert0 aiMarcusenius desertusi sp nov Teleostei Mormyridae a mormyrid fi cJul-03-2016 a1 - 183 a

We critically compared Marcusenius specimens from the mouth of the Cunene River on the Namibia/Angola border, a harsh desert environment on the Atlantic Ocean coast virtually devoid of aerial insects with aquatic larvae which are an important food item, with Marcusenius multisquamatus Kramer & Wink, 2013 from the escarpment region of that same river, in a relatively rich and productive subtropical savannah environment. River mouth specimens were differentiated in morphology and electric organ discharges, as determined by ANOVA/MANOVA comparisons, principal component and discriminant analyses on morphological and electrophysiological characters, and genetics, including sequences of the mitochondrial cytochrome b gene, indicating reproductive isolation. Specimens from the river mouth differed from M. multisquamatus, their closest relatives, by having a shorter snout, a smaller eye diameter, and smaller nares separation. River mouth specimens were also differentiated from other, increasingly less-close relatives, such as M. altisambesi Kramer et al., 2007 from the Okavango River, Botswana, and from M. krameri Maake et al., 2014 from the Limpopo System, South Africa. We therefore designate the new species Marcusenius desertus sp. nov. for the Cunene River mouth population.

10aecology10aelectric organ discharges10agenetic differentiation10amorphology10aphylogeography10aspeciation1 aKramer, Bernd1 avan der Bank, F., Herman1 aWink, Michael uhttp://www.tandfonline.com/doi/full/10.2989/16085914.2015.1137855