Nimbapanchax leucopterygius, Sonnenberg, Rainer & Busch, Eckhard, 2009

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 : 11-14

Nimbapanchax leucopterygius , new species

( Figs. 4 C&D, 5A–D; Table 3 )

Misidentification as: Aphyosemion cameronensis var. obscurus (non Ahl, 1924), Aphyosemion liberiense (non Boulenger, 1908), Aphyosemion maeseni non Poll, 1941, Archiaphyosemion maeseni (non Poll, 1941), Roloffia maeseni (non Poll, 1941).

Holotype. ZFMK 41481, male, 43.6 mm SL, Guinea, Foret Classeé de Dieke, southeastern Guinea (7° 28.70' N, 8° 50.45' W), collection locality GF 06/6, E. Busch and B. Wiese, 16 May 2006.

Paratypes. ZFMK 41482–41483, 2 females, paratopotypes, collected with holotype. MRAC 73-39- P- 1897–1904, 4 males, 4 females, Guinea, N'zerekore, H. Olsen, November 1963 – February 1964. MRAC 75- 26- P- 01–04, 2 males, 2 females, Liberia, Salayea (7° 37' N, 9° 30' W), E. Roloff, 1971. MRAC 81-19- P- 114– 116, 2 males, 1 female, Cote d'Ivoire, riviertje buiten Déoulé, zijriviertje van de Kilo op secundaire weg van Man naar Biankouma (rivulet near Déoulé, small tributary of the Kilo River, on secondary road from Man to Biankouma), H. De Breuyn, 24 July1980.

Diagnosis. Nimbapanchax leucopterygius ( Figs. 4 C&D, 5A–D) is distinguished, together with all other congeneric species, from the related Archiaphyosemion , Callopanchax , and Scriptaphyosemion by the combination of characters as given in the generic diagnosis. Nimbapanchax leucopterygius and N. melanopterygius new species ( Figs. 6A –D) are distinguished, together with N. viridis ( Figs. 7A –D), and N. jeanpoli ( Figs. 8A &B), from N. petersi ( Figs. 9A &B) and A. guineense ( Figs. 10A –D) by a white or light blue margin around caudal fin (not always completely closed), a small dark brown or reddish submarginal stripe and brown blotches between fin rays, no yellow zone in fins, females without or with small spaced dark bars on side versus an often broad yellow to yellow-greenish or whitish marginal or submarginal zone on anal and lower caudal fin, females on side with wide spaced dark bars in N. petersi and an asymmetrically colored caudal with white upper and lower margin, a dark brown or red submarginal line and alternating white and brown or red streaks from center to posterior fin margin, sometimes fin center blue-greenish and alternating pattern only in posterior caudal fin in A. guineense . Nimbapanchax leucopterygius is, together with N. melanopterygius , new species, N. petersi , N. viridis , and A. guineense , distinguished from N. jeanpoli by the lack of broad brown or red-brown vertical bars or blotches on side in males. It is, together with N. melanopterygius , new species, distinguished from N. viridis and N. jeanpoli by brown sides of males with center of many scales metallic blue-green, only little red pigmentation on head and sides and a dark brown or red blotch above and slightly posterior to the insertion of pectoral fin on side in females versus blue-green scales with only narrow brown scale margins on the side of males with distinct red dots forming lines or horizontal stripes in N. viridis or the before mentioned brown or red-brown vertical bars or blotches on upper half of side in N. jeanpoli , and no dark blotch above insertion of pectoral fin in females. It is distinguished from N. melanopterygius , new species, by a white or light blue margin and a dark brown or red submarginal band in the anal fin and a blue-green center in unpaired fins with small dark brown or red dots versus a black, dark brown, or dark red marginal, sometimes white submarginal band in anal fin and a less dense pattern of brown or dark red blotches in anal and caudal fin in N. melanopterygius . Nimbapanchax leucopterygius is distinguished from A. guineense , N. melanopterygius , N. jeanpoli and N. viridis by a pattern of vertical stripes on sides formed by metallic blue-greenish scales in young males and a similar pattern of brown stripes in females versus absence of vertical striped pattern or broad, dark brown stripes or blotches on upper half in N. jeanpoli , and vertical stripes only faint in frightened females of N. melanopterygius .

Description. See Figures 5A –D for overall appearance and Table 3 for morphometric data of the type series. Nimbapanchax leucopterygius shows sexual dimorphism; adult males, on average, are more colorful and larger than females. A cylindrical, laterally slightly compressed and elongate medium sized nothobranchiid species. Dorsal profile straight on head, slightly convex from nape to caudal peduncle, greatest body depth approximately at base of pelvic fin. Ventral profile slightly convex from head to end of anal fin base, caudal peduncle slightly concave. Snout slightly pointed, mouth directed upwards, lower jaw longer than upper, posterior end of rictus at same level as or slightly above center of eye.

Closed frontal neuromast system with one groove, preopercular neuromast system with 5 pores, the apomorphic condition for the Epiplateinae ( Clausen 1966, 1967; Van der Zee 2002).

Total number of vertebrae 29–30, number of vertebrae with pleural ribs 14, with haemal spines 15–16 (holotype and two paratypes).

Dorsal and anal fins in males slightly pointed; caudal fin rounded, no filamentous extensions. Fins in females generally smaller and more rounded. Basal part of fins covered with an opaque mucus film. Dorsal and anal fins located posterior to mid-body. First dorsal fin ray behind origin of anal fin, situated above anal fin ray 6–8. Dorsal fin rays 10–14; anal fin rays 15–18. The lowest values of 10 dorsal and 15 anal fin rays with origin of dorsal fin above anal fin ray 8 were found only in a single female, all other specimens have 13– 14 dorsal and 16–18 anal fin rays with origin of dorsal above anal fin ray 6–7. Pectoral fin extending posteriorly, not reaching origin of pelvic fin; pelvic fin not or just reaching anal fin. Pectoral fin rounded.

Scales cycloid; body and head entirely scaled, except for ventral surface of head. Frontal squamation of G-type; scales on lateral line 28–30 + 3–4 on caudal fin base, not all scales with small grooves in center. Transverse rows of scales above pelvic fin 9–10; circumpeduncular scale row 13–14.

Live coloration. Males with sides dark brown, some scales in center blue-green or copper ( Figs. 5A &B). In young males a vertical pattern of metallic blue-green and brown bars, in older males scales with brown margin and blue green center forming a reticulated pattern. Back brown, belly grayish to light brown. Head brown, scales with dark brown margin, on opercle and slightly posterior red pigments on scales, above or slightly posterior to insertion of pectoral fin dark brown or red blotch. Ventral side of head dark gray or graybrown. Unpaired fins in center blue-green with more or less regular brown dots or stripes, white or light blue fin margins, dark submarginal zone. Pelvic fins similarly colored as anal fin, pectoral fins hyaline with whitish to blue-greenish margin.

Females with sides brown, center of scales often light brown, dark scale margin, forming a reticulated pattern ( Fig. 5 C). Behind opercle, above and slightly posterior to insertion of pectoral fin a dark brown or red blotch, followed posteriorly by dark brown bars. Back brown, belly light brown. Unpaired fins in center bluegreen or greenish with dark dots between fin rays, with faint whitish margin and submarginal dark zone. Pelvic fins similarly colored as anal fin, pectoral fins hyaline.

Coloration in ethanol. Males shortly after preservation side and back dark gray or brown, belly lighter brown, scale borders dark, forming a reticulated pattern ( Fig. 5 D). Unpaired and pelvic fins grayish dark with whitish margin. Pectoral fins pale dark gray, paler on margin.

Females are similar to males and same as juveniles ( Fig. 5 D). On freshly preserved females dark vertical bars on sides. Fins dark gray, unpaired fins with white margin, paired fins with pale gray margin.

Etymology. The species name was chosen with regard to the characteristic white margin of the anal fin, from the greek leucos = white and pterygion = diminutive of pteryx = fin or wing.

Distribution and habitat. Nimbapanchax leucopterygius is known from a large area in northeastern Liberia, southeastern Guinea and western Ivory Coast ( Fig. 1 ). Most probably all localities in the literature, which mention the occurrence of Archiaphyosemion maeseni , belong to this species (e.g., Berkenkamp & Etzel 1977; Etzel 1974a, b, 1992, 1993; Huber 1982, 2000; Paugy et al. 1990; Teugels et al. 1988; Wildekamp 1993; Wildekamp & Van der Zee 2003). Some records of S. liberiense are, according to Huber (1982), at least in part a misidentification of Archiaphyosemion or Nimbapanchax species and several might belong to N. leucopterygius . According to published pictures or live specimens from collections in Guinea, Liberia and Ivory Coast (e.g., Berkenkamp & Etzel 1977; Etzel 1974a, b; Seegers 1997) the color pattern variability within the species is low and all populations show the typical white or light blue margin on the anal fin.

The type locality is a small, slow flowing creek in the rainforest, covered by tree canopy. The water was slightly brownish stained, water temperature 20°C, maximum depth about 40 cm.

Figures

FIGURE 1. Distribution map of Archiaphyosemion and Nimbapanchax: A. guineense collections are indicated by a grey circle, N. petersi by a black circle, N. jeanpoli by a grey square, N. viridis by a black square, N. leucopterygius by a grey triangle, and N. melanopterygius by a black triangle. The actual species distribution will in fact be broader based on records not associated with vouchered specimens.

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).

FIGURE 6. A. Nimbapanchax melanopterygius, male paratype, locality GF 06 / 1, Guinea; B. Nimbapanchax melanopterygius, male holotype, locality GF 06 / 2, Guinea; C. Nimbapanchax melanopterygius, female paratype, locality GF 06 / 1, Guinea; D. Nimbapanchax melanopterygius, male holotype (42.9 mm SL), locality GF 06 / 2, and female paratype (42.4 mm SL), locality GF 06 / 1, Guinea, photographed short after preservation.

FIGURE 7. A. Nimbapanchax viridis, male from locality GF 06 / 5, Guinea, not preserved. B. Nimbapanchax viridis female from localitiy GF 06 / 5, Guinea, not preserved. C. Nimbapanchax cf. viridis, male from locality GF 06 / 8, Guinea, not preserved. D. Nimbapanchax cf. viridis, female from locality GF 06 / 8, Guinea, not preserved.

FIGURE 8. A. Nimbapanchax jeanpoli, male from locality GF 06 / 11, Guinea, not preserved. B. Nimbapanchax jeanpoli, female from locality GF 06 / 11, Guinea, not preserved.

FIGURE 9. A. Nimbapanchax petersi, male, aquarium strain from Banco Park, Ivory Coast, not preserved. B. Nimbapanchax petersi, female, aquarium strain from Banco Park, Ivory Coast, not preserved.

FIGURE 10. A. Archiaphyosemion guineense, male, aquarium strain SL 03 / 16, Sierra Leone, not preserved. B. Archiaphyosemion guineense, male, collection locality GF 06 / 9, Guinea, not preserved. C. Archiaphyosemion guineense, male, collection locality GF 06 / 11, Guinea, not preserved. D. Archiaphyosemion guineense, female, collection locality GF 06 / 9, Guinea, not preserved.

FIGURE 5. A. Nimbapanchax leucopterygius, male holotype, collection locality GF 06 / 6, Guinea; B. Nimbapanchax leucopterygius, juvenile F 1 male, GF 06 / 6 strain, Guinea, not preserved; C. Nimbapanchax leucopterygius, female paratype, collection locality GF 06 / 6, Guinea; and D. Nimbapanchax leucopterygius, male holotype (43.6 mm SL) and female paratype (42.8 mm SL), locality GF 06 / 6, Guinea.