Fenerbahce devosi, Sonnenberg, Rainer, Woeltjes, Tonnie, Van, Jouke R. & Zee, Der, 2011

Sonnenberg, Rainer, Woeltjes, Tonnie, Van, Jouke R. & Zee, Der, 2011, Description of Fenerbahce devosi (Cyprinodontiformes: Nothobranchiidae), a new species of dwarf killifish from the eastern Congo Basin in the Democratic Republic of Congo, Zootaxa 2966, pp. 1-12 : 4-10

Fenerbahce devosi , new species

( Figs. 2–4 ; Table 3)

Adamas sp. Van der Zee, 1990: 71–75.

Adamas formosus (in part) Wildekamp, 1993: 13 –14.

Holotype. MRAC 2008-19 -P-1, 1 male, 23.6 mm SL, Democratic Republic of Congo, ~ 67 km south from the ferry across the Congo River at Kisangani, towards Ubundu on the road R410, Ruiki River drainage, collection locality AVD 2007/2, collected by the local people for J. Musafiri and A. Van Deun, 22 Oct. 2007.

Paratypes. MRAC 2008-19 -P-2–3, 2 males, 21.6–25.9 mm SL, Democratic Republic of Congo, ~ 7 km north of Ubundu, along the railway to Kisangani, in small brooks, Ruiki River drainage, collection locality AVD 2007/1, collected by the local people for J. Musafiri and A. Van Deun, 22 Oct. 2007. MRAC 2008-19 -P-4–5, 2 males, 24.9– 25.9 mm SL, paratopotypes, collected with holotype.

Non-types. MRAC 87-42-P-1609–611, specimens in poor condition, not measured, Democratic Republic of Congo, Amabobi River, affl. of Congo River, left bank, km 69 on Kisangani to Ubundu route, L. De Vos & A.

Kimbembi, 22 Mar. 1987. MRAC 89-43-P-705–714, sex of specimens unclear, in poor condition, 14.0– 21.5 mm SL, Democratic Republic of Congo, Lubilu River, left bank, km 82 old route from Kisangani to Ubundu, L. De Vos & A. Kimbembi, 0 3 Jan. 1989.

DNA samples: RS1786, 1 male, AVD 2007/1, same data as MRAC 2008-19 -P-2–3; RS 1788, 1 female, AVD 2007/2, same data as holotype. Both DNA sample and associated voucher specimens are deposited in the DNA- and tissue collection of the ZFMK.

Diagnosis. Fenerbahce devosi ( Figs. 2–4 , Table 3) shares the following combination of characters with F. fo rmosus ( Fig. 5 , Table 3): small species with maximum TL below 4 cm, reflective scales dorsally on the head, complete absence of tubular structures in the pre-, post-, supraorbital, and opercular neuromast system, and small dorsal fin.

Huber (1979) and a specimen from a collection near Oyo, which have a more northern distribution, whereas F. f o r m o s u s S indi-

cates samples from the southwestern distribution area, closer to Kinshasa, from Pool Malebo and the Njiri River (see Fig. 1 ).

Abbreviations: TL = total length, SL = standard length, HL = head length, BD = body depth, E = eye diameter, S = snout

length, pD = predorsal length, pA = preanal length, CL = caudal peduncle length, CD = caudal peduncle depth, CPR = caudal

peduncle length/depth ratio, D = number of dorsal fin rays, A = number of anal fin rays, D/A = position of first dorsal fin ray

relative to the opposite anal fin ray. SL in mm, TL, HL, BD, pD, pA, CL, and CD as percentages of SL; E, and S are given as

percentages of head length. Numbers in brackets are mean values.

Western clade (19 specimens) Eastern clade (36 specimens)

F. f o r m o s u s N F. formosus S Tshuapa river F. devosi F. sp. aff. devosi Epulu East Congo

river**

* values of only 2 specimens out of 14, counted on X-ray images, all other specimens not countable. ** values only from one specimen.

All Fenerbahce specimens can be divided by the combination of several morphological characters into two clades: the western clade includes the populations from Voula to the Tshuapa River, the eastern clade the populations from the Aruwimi River to Nikambwe and Epulu. The western clade differs from the eastern clade by a more posterior insertion of the dorsal fin in relation to the anal fin (D/A = 1/10–14 versus D/A = 1/7–10); a slightly lower number of vertebrae (25–26 [except in F. sp. ‘Tshuapa' 28–29] versus 27–30); a fused hypural fan or both hypural plates only on posterior 20% not fused versus both hypural plates not or only on anterior half fused; a mean lower number of caudal fin rays attached to hypural plates or fan (mean = 8.11, range = 8–9 versus mean = 9.71, range = 9–10).

Fenerbahce devosi is distinguished from F. formosus by the combination of the following characters: a more robust species, observed maximum TL larger (largest observed male, kept in an aquarium, approximately 38 mm TL, not preserved, largest value given for F. formosus is 30 mm [ Radda & Pürzl 1987]); dorsal fin inserts in a more anterior position compared to the anal fin (D/A = 1/8–9) versus a more posterior inserted dorsal fin in F. f o r m o s u s (D/A = 1/10–14). Fenerbahce devosi has a deeper body then F. formosus , body depth as percentage of standard length ranges from 21.7–23.2 in F. devosi and from 17.9–21.2 in F. formosus . Extensions of the edges of caudal fin can be almost as long as the fin itself in adult males, in F. formosus caudal fin extensions are only half the length of the caudal fin.

Body colour of males on sides yellow-green to blue-green, unpaired fins in centre blue-green to greenish versus body pale-blue to silvery and centre of unpaired fins light blue in F. formosus .

Anal fin orange to yellow-greenish, with a row of red dots at anal base and vague orange edge in F. d e v o s i versus pale blue with basal red stripe and discrete red edge in F. formosus . Southern populations of F. f o r m o s u s with red spots and/or stripes in middle section of anal fin. Lower half of caudal fin orange to yellow-greenish versus pale blue in F. formosus . Dorsal fin spotted at base in F. d e v o s i versus a red basal stripe and complete fin spotted with inter radial red stripes in F. formosus . Caudal fin spotted without inter radial red stripes in F. devosi versus spotted with inter radial red stripes in F. f o r m o s u s. Pelvic fin like anal fin, yellow to blue-green with red border in F. devosi versus pale blue with red border in F. f o r m o s u s. Pectoral fin in males transparent with an orange or yellow hue and small blue border versus transparent with a light blue distal edge.

Fenerbahce devosi is distinguished from F. sp. ‘Epulu’, F. sp. ‘East Congo’ and F. sp. ‘Tshuapa’ by a deeper body and a shorter head, and from F. sp. aff. devosi by some small differences in measurements and male colouration (see Table 3 & Fig. 6 ).

Description. See Figures 2–4 for general appearance and colour pattern and Table 3 for morphometric data of the type series. Small nothobranchiid species, largest observed specimen in the type series 31.1 mm TL. Strong sexual dimorphism, adult males are larger and more colourful than females and have larger unpaired fins with extended rays, especially in the caudal fin.

Dorsal profile straight or slightly convex, greatest body depth at base of pelvic fin, ventral profile slightly convex. Snout rounded, mouth directed upwards, lower jaw longer than upper jaw, posterior end of rictus at level of dorsal third of eye.

Frontal neuromasts in two separate grooves, pre-, post-, and supraorbital neuromast system and upper two pit organs of the preopercular neuromast system lack tubular structures. Two supraorbital grooves with three neuromasts each. Anterior most neuromasts of supraorbital system in line with frontal neuromasts. All neuromasts are situated in more or less shallow grooves or simply on top of the skin.

Teeth on jaws unicuspid, outer row large and curved, inner teeth smaller and more irregularly placed. Considerable variation in width of vomer and parasphenoid.

For two specimens we counted a total number of vertebrae 27 or 28; the hypurals 1 & 2 and 3–5 are fused in two hypural plates, both hypural plates in anterior half fused; ten caudal fin rays attached to hypural plates.

Scales cycloid, body completely scaled except ventral head surface. Frontal squamation of G-type. Typical for the genus are the silvery scales on top of the head just behind the level of eyes. No scales on dorsal and anal fin base. Two or three scale rows on caudal fin base. Scales on mid longitudinal series 26–30, transverse series of scales before dorsal fin 9, 12 circumpedunclar scale rows.

All unpaired fins pointed in males, older males show elongated rays at the caudal fin edges. Number of dorsal fin rays 8–10, anal fin rays 14–16; first dorsal fin ray above anal fin ray 8–9. Fins in females smaller and rounded. Pectoral fin not or just reaching pelvic fin.

Colouration. Live specimens. Males ( Figs. 2 & 3 ). Side of body yellow- to blue-green, metallic copper dorsally. Most scales on side with a red spot forming up to seven horizontal lines. These are sometimes interrupted, especially the anterior part of the lower lines. Dorsal side copper to brown coloured, ventral from chin to pelvic fin pale whitish. On head just posterior of eyes metallic silvery scales. Three red streaks on opercle in an approximate 45° angle, lower red streak behind the eye reduced to a red spot.

Dorsal fin green-blue to blue with more or less complete dark red margin; red spots between fin rays at the fin base; anterior part of dorsal fin only with spots at the base, posterior part with small red spots or short streaks. Anal fin yellow- to blue-green with orange distal part and red-orange margin; a row of red spots at the fin base. Upper half of caudal fin blue-green, lower half yellow to orange, centre greenish; caudal fin with red spots especially in the centre of the fin, fusing to small streaks in posterior part; all caudal fin edges with red margin, fin extensions yellow. Pectoral fin hyaline with orange hue; pelvic fin yellow to orange with dark red margin.

Females ( Fig. 4 ). Body light brown to grey-brownish, dorsally darker and ventrally light brown. Scales on sides with a dark border, forming a reticulated pattern. Most scales on dorsal half of sides with a small red dot. All fins hyaline, only some scattered red dots.

DNA results. The resulting alignment of the 16S rDNA is 501 bp long, including one insertion/deletion (indel), the cytochrome b alignment 776 bp, translating to 252 amino acids, and the 28S rDNA alignment has a length of 1,173 bp and no indel. The complete alignment for the analysis consists of 2,450 bp. The 16S rDNA alignment contains 31 variable and 29 informative positions, the cytochrome b alignment 93 variable and 82 informative positions, and the 28S rDNA alignment 8 variable and 7 informative positions. The complete alignment has 132 variable and 118 informative positions. The mitochondrial sequences show the typical anti G-bias of this organelle genome ( Zhang & Hewitt 1996). Uncorrected pairwise distances were given in Table 2, the resulting tree with bootstrap support values in Figure 7 . The six specimens from four localities ( Fig. 1 , Table 2) are placed in three distinct clusters. Two males from Voula show no genetic differences, whereas the third specimen, a female, is by nuclear and mitochondrial DNA genetically closer to the sample from Pool Malebo ( Fig. 7 ). The two specimens of F. devosi are clearly separated from all F. formosus samples. The sequence divergence between F. d ev o s i and the specimens in the two clusters assigned to F. formosus is approximately two times the maximum observed divergence within F. f o r m o s u s.

Distribution. The genus Fenerbahce is distributed from Voula at the lower Congo and Pool Malebo in the west to the Portes de l’Enfer in the southeast of the Congo River basin ( Fig. 1 ). Cyprinidontiform fishes collected in 1925 at Capelongo, Cunene River, in Angola (AMNH 8994), and later identified as Adamas formosus turned out to be a poeciliid species after examination of a picture of these specimens kindly sent by M. Stiassny to the authors.

Fenerbahce devosi is, according to our current knowledge, restricted to the eastern part of the Congo Basin with all known populations near Ubundu. Other populations (e.g., Yangambi, Yaekama, Epulu, and Nikambwe) differ in certain characters and are therefore not included in this species. During a recent survey of the Congo ichthyofauna, a new collection of Fenerbahce was made by MRAC scientists (E. Vreven, pers. comm.) at the mouth of the Aruwimi River, east of Basoko ( Fig. 1 ), which at the moment only could be studied by photographs ( Fig. 6 ). These specimens differ by certain male colour pattern characters considerably from F. devosi , so we hesitate to include it within this species without further research. However, the available pictures indicate, that it also belongs to the Fenerbahce species of the eastern Congo Basin, indicated by the position of the dorsal fin with regard to the anal fin.

Etymology. Fenerbahce devosi is named after Luc De Vos, head of the Ichthyology department of the National Museums of Kenya, who died far too young in 2003. Luc made several important fish collections in the Congo Basin, including populations of F. devosi .

Figures

FIGURE 1. Collection point map of Fenerbahce based on specimens and data from the MRAC collection, U. Schliewen (pers. comm.), W. Kirchhof (pers. comm.), Huber (1979, 2007 b), and Van der Zee (1990).

FIGURE 2. Male of Fenerbahce devosi, collection locality AVD 2007 / 1, not preserved. Photographed by H. Ott.

FIGURE 3. Male of Fenerbahce devosi, collection locality AVD 2007 / 2, not preserved. Photographed by H. Ott.

FIGURE 4. Female of Fenerbahce devosi, collection locality AVD 2007 / 2, not preserved. Photographed by H. Ott.

FIGURE 5. Males of Fenerbahce formosus from different localities: A. aquarium strain, originating from Pool Malebo, Democratic Republic of Congo, not preserved. Photographed by A. Persson. B. F 1 offspring from specimens collected at the Njiri River, Republic of Congo, not preserved. Photographed by H. Ott. C. wild caught specimen from Oyo, Republic of Congo, not preserved. D. second generation offspring of an aquarium strain originating from Tchika Pika, Republic of Congo, not preserved. C and D photographed by T. Woeltjes.

FIGURE 6. Male of Fenerbahce sp. aff. devosi, photographed shortly after capture, mouth of the Aruwimi River east of Basoko. Photographed by T. Musschoot.

FIGURE 7. Unrooted tree of the maximum parsimony analysis of the DNA dataset. Numbers on internal nodes are bootstrap support values. Tree description: tree length = 131, consistency index = 0.9542, homoplasy index = 0.0458, retention index = 0.9535, rescaled consistency index = 0.9098. Scale bar indicates the number of steps.