Epiplatys maeseni ( Poll, 1941 ) Poll, 1941

Sonnenberg, Rainer & Busch, Eckhard, 2009, Description of a new genus and two new species of killifish (Cyprinodontiformes: Nothobranchiidae) from West Africa, with a discussion of the taxonomic status of Aphyosemion maeseni Poll, 1941, Zootaxa 2294, pp. 1-22 : 10-11

Epiplatys maeseni ( Poll, 1941) , new combination

( Figs. 4A&B )

Synonymy. Aphyosemion maeseni Poll, 1941 : p. 141

Material examined. Aphyosemion maeseni : holotype, MRAC P- 66392, 37 mm TL; collected at the confluent of the small Masei River and the Bon de Boan River, which is a tributary of the Nuon (at the border Liberia – Ivory Coast); A. Maesen, F. M. Olbrechts & P. J. Vandenhoute, 12–13 April 1939. Epiplatys olbrechtsi : syntypes, MRAC P- 66388–66391, same data as Aphyosemion maeseni . Additional material see below.

Diagnosis. The holotype is, as far as it can be assessed by its present state of conservation, by external morphology similar to the syntypes of Epiplatys olbrechtsi Poll, 1941 , having a robust and more rounded body versus more slender and laterally slightly compressed in Nimbapanchax . It shares with Epiplatys olbrechtsi the distinct morphology of the throat and lower jaw, diagnostic for Epiplatys , which differs considerably from the head morphology of Archiaphyosemion , Nimbapanchax and other nothobranchiid genera ( Figs. 4 C&D) (see Van der Zee 2002; Wildekamp & Van der Zee 2003). In Epiplatys the opercle borders on the ventral side have their smallest distance at or slightly posterior of the eye level and then widen anteriorly on the lower jaw ( Figs. 4A,B ,E&F). In the remaining Epiplateinae the opercle borders on the ventral side run almost parallely towards the anterior part of the lower jaw ( Figs. 4 C&D). Epiplatys maeseni has a short and more rounded snout versus longer and more pointed in Epiplatys olbrechtsi ( Figs. 4 E&F).

Coloration. Preserved in ethanol. Body nearly completely uniform brownish, unpaired fins darker brown. No traces of color pattern visible, no whitish or light border on unpaired fins. Poll (1941) reported black or dark dots in the dorsal fin.

Distribution. Currently only known from the type locality in northwestern Ivory Coast. All previous records in the literature, which mention maeseni under the generic names Aphyosemion , Roloffia or Archiaphyosemion most probably are dealing with N. leucopterygius , new species, and at least were a record for a Nimbapanchax species and not an Epiplatys .

Etymology. The species was named after one of the collectors, A. Maesen.

Remarks. The single type specimen of Aphyosemion maeseni (MRAC P-66392) was compared with specimens from other localities from Guinea, Liberia and Ivory Coast, which are currently regarded as conspecific (see list of material under the respective descriptions below). All characters that distinguish the type of A. maeseni from Nimbapanchax are shared with the syntypes of E. olbrechtsi , with the exception of the snout shape, which is slightly shorter and more rounded in E. maeseni ( Figs. 4A&B ). However, it is possible that the type is a damaged or deformed specimen of E. olbrechtsi or might represent a second Epiplatys species within the same collection. Unfortunately no useful traces of color patterns are visible. The current assignment of a Nimbapanchax species to the name Aphyosemion maeseni seems to be based on the dark coloration of the unpaired fins mentioned by Poll (1941). However, Poll (1941) and later Scheel (1968, p. 289) did not mention the white border of all unpaired fins, typical for the Nimbapanchax species for which the name is currently used. With regard to the morphological characters, the type of Aphyosemion maeseni represents an Epiplatys species, and the Nimbapanchax species for which this name is currently in use represents a scientifically unnamed species, which is described in the following. Until a revision of Epiplatys might show its synonymy with another species, the new combination Epiplatys maeseni ( Poll, 1941) is an available name.

Figures

FIGURE 4. A & B. Ventral and lateral view of the holotype of Epiplatys maeseni (MRAC P- 66392), 37 mm TL; C & D. Ventral and lateral view of a paratype of N. leucopterygius (MRAC 73 - 39 - P- 1897); 58 mm TL; and E & F. Ventral and lateral view of a syntype of E. olbrechtsi (MRAC P- 66388), ca. 55 mm TL (Photos by T. Musschoot, MRAC).