Morphological convergences between African and South American electric fishes.

<p>Mormyroid African electric fishes (left column) are facing gymnotiform South American electric fishes (right column) with similar aspects of morphology (such as elongate bodies, extended tube-like snouts, reduced eyes, and/or small mouth sizes). Anterior portion of body shown above small image of whole body (except for <i>Petrocephalus sullivani</i>); electric organ discharge waveform shown for every species (each trace 5 ms in total duration with head-positivity plotted upwards). (<b>A</b>) <i>Mormyrops zanclirostris</i>, 175 mm standard length (SL), Ivindo River, Gabon, (<b>B</b>) <i>Sternarchorhynchus oxyrhynchus</i>, 220 mm total length (TL), Rio Negro, Brazil; (<b>C</b>) <i>Mormyrus proboscirostris</i>, 232 mm standard length, Ubundu, Congo River, D.R. Congo; (<b>D</b>) <i>Rhamphichthys</i> sp., 305 mm TL, Rio Negro, Brazil; (<b>E</b>) <i>Mormyrops anguilloides</i>, 195 mm SL, Yangambi, Congo River, D.R. Congo; (<b>F</b>) <i>Gymnotus</i> sp., 195 mm TL, Rio Negro, Brazil; and (<b>G</b>) <i>Petrocephalus sullivani</i>, Ogooué River, Gabon; (<b>H</b>) <i>Eigenmannia</i> sp., Apure River, Venezuela. Species A–D feed on benthic invertebrates, species E, F are piscivorous, and G, H feed on pelagic invertebrates.