Mormyridae

Neumann, Dirk, Obermaier, Henriette & Moritz, Timo, 2016, Annotated checklist for fishes of the Main Nile Basin in the Sudan and Egypt based on recent specimen records (2006 - 2015), Cybium 40 (4), pp. 287-317 : 293

Mormyridae

Eleven of fifteen Nile mormyrids have been confirmed during our surveys, with Pollimyrus isidori (Valenciennes, 1847) being the most common one. Large Mormyrus niloticus (Bloch & Schneider, 1801) , Mormyrus kannume Forsskål, 1775 , Mormyrops anguilloides (Linnaeus, 1758) (> 600 mm TL) and Hyperopisus bebe (Lacepède, 1803) (> 400 mm TL) are common during flood season in fish markets in Khartoum. Petrocephalus species seem to be rare and are confirmed with only four individuals despite intensive search. Apparently, populations dropped significantly since Sandon (1950), who reports that P. bane (Lacepède, 1803) was the most common mormyrid species throughout the year in the Nile below Khartoum.

Pollimyrus isidori seems to vary remarkably in body shape and colouration: smaller specimens tend to be more elongated; larger specimens sometimes grow rather deepbodied and nearly round if viewed laterally. The body colouration in Nile populations may range from a complete silver body without any spots, to a silver and intensively spotted body with intensive purple hue on the flanks, sometimes in combination with an intense bright steel blue back. Irregular dark blotches seem to vary individually and may densely cover almost the entire body. Observed variability in EODs of 62 Nile specimens largely concurs with the heterogeneity of signals in West African P. isidori ( Moritz et al., 2008) and currently does not allow further conclusions on the status of specific populations in the Nile.