The genus Episemion was described in 1987 based by five specimens found by Peter Wagner and Roland Wendel in 1986 and by Radda & Pürzl in 1987.

Thus far only one species in the Genus has been described, E. callipteron Radda & Pürzl, 1987 from a small range that covers northwestern Gabon and southeastern Equatorial Guinea. A slightly different form with an aberrant color pattern was found in Edoum in Nordgabun on the border with Gabon in south Equatorial Guinea. Radda and Pürzl wrote in their introduction that the referring this species to a specific Genus was problematic.

When comparing the dorsal and anal ray values and the position of the dorsal to the anal with all known subgenera, nothing matched.

Only a few Nothobranchius species have the similar values.

The tail fin shape is striking and only shared with Fundulosoma.

Drawing and coloring pattern correspond rather that of the genus Epiplatys

The diagnostic for deciding referral of the Genus name to either the Aplocheilinae or the Nothobranchiinae per Parenti (1981) are these criteria: 1. Rear vomer area wide at Epiplatys, very narrow in Aphyosemion 2. Epipleural ribs unharmed Epiplatys (Fig. 1 top right), feared at Aphyosemion (Fig. 1 bottom right) 3. Upper Hypuralia shared with Epiplatys, undivided at Aphyosemion 4. Absence (Epiplatys) or presence (Aphyosemion) of curved processes on the fourth epibranchialia. 5. High (Epiplatys) or low Chromosome number (Aphyosemion) 1 - 4 are only for skeletal preparations determine. Radda & Pürzl had only 5 Animals available as types should be available. That's why they could meet those criteria to not confirm. Episemion was provisional by the authors described as a subgenus of Epiplatys. In investigations of the relationship a strange representative of the Aplocheilidae (Fundulopanchax powelli), caught in the western Niger Delta the author has reviewed many features, around Aphyosemion and Fundulopanchax to be able to distinguish (Van der Zee & Wildekamp, ​​1995). In these studies are also EpiplatysArten and Episemion callipteron Service. It turned out that Epiplatys and Episemion have very little in common. These results were however in the F. powelli description not published and are therefore presented here. skeleton Rear Vomer area The vomer (a tiny bone on the Underside of the skull) is at Episemion narrow, just like Aphyosemion. Epipleural ribs furrowed