Chromaphyosemion koungueense, Rainer Sonnenberg, 2007

Rainer Sonnenberg, 2007, Description of three new species of the genus Chromaphyosemion Radda, 1971 (Cyprinodontiformes: Nothobranchiidae) from the coastal plains of Cameroon with a preliminary review of the Chromaphyosemion splendopleure complex., Zootaxa 1591, pp. 1-38 : 7-11

Chromaphyosemion koungueense sp. nov.

(Figs. 3-6)

Aphyosemion bivittatum (non Lönnberg, 1895), Scheel 1968: 117-127 (in part, distribution, morphology, taxonomy, synonymy), 1974: 47-98 (in part, BIV-DI strain, BIV-NN strain, color pattern, crossing experiments, distribution, karyotypes).

Aphyosemion (Chromaphyosemion) bitaeniatum (non Ahl, 1924), Scheel 1990: 168-173 (in part, distribution, karyotypes, taxonomy).

Aphyosemion (Chromaphyosemion) splendopleure (non Brüning, 1929a), Agnèse et al. 2006 (phylogeny, collection localities, taxonomy), Amiet 1987: 49, 176, plate 36, figs. 13 and 14 (in part, collection localities, color pattern), Huber 1998a: 20-21 (in part, taxonomy, distribution), 2000: 471 (in part, collection localities), Legros & Zentz 2007: 20-21 (phylogeny), Radda & Pürzl 1982: 24-25 (in part, distribution), Radda & Pürzl 1983: 20-21 (in part, distribution) 1987: 70 (in part, distribution), Seegers 1981: 159, 161 (in part, distribution), 1986: 52-54 (in part, distribution), 1997: 122 (color photo, male from Douala), Wildekamp 1993: 277-279 (in part, distribution).

Aphyosemion (Chromaphyosemion) splendopleure phenotype Dizangue (non Brüning, 1929a), Eberl 1996: 50 (color pattern, collection localities, color photo p.1), Eigelshofen 1998: 10-12 (distribution, color photo).

Chromaphyosemion splendopleure phenotype 'Dizangue ' (non Brüning, 1929a), Legros et al. 2005:16-17 (color pattern, distribution, phylogeny).

Chromaphyosemion sp. aff. splendopleure 'Dizangue', Sonnenberg 2000: 81, 85 (color pattern, distribution, color photo Nr. 3).

Holotype. ZFMK 39949 , male (24.3 mm SL), Cameroon, at the road from Edea to Dizangue and Ndonga, in the Koungue , a small river in the forest near the village Koungue Ndonga (03°48'36.9'' N, 09°55'03.9'' E), U. Kämpf, R. Sonnenberg, and A. Tränkner leg., collection locality CMM 3.

Paratypes. ZFMK 39950-39955 (2 males, 3 females, 1 juvenile), paratopotypes, collected with the holotype .

ZFMK 39956-39957 (2 males), Cameroon, a small creek crossing the road Mbambou to Mouanko, some kilometers in oil palm plantation in direction Mouanko (03°42'48.8'' N, 09°51'28.2'' E), H. Kullmann and M. Völker leg., collection locality KV 03/14.

ZFMK 39958-39959 (2 males), Cameroon, near the road from Edea to Kribi (03°32'28.9'' N, 10°05'12.1'' E), U. Kämpf, R. Sonnenberg and A. Tränkner leg., collection locality CMM 8.

ZFMK 39960-39964 (3 males, 2 females), Cameroon, a small creek crossing the road from Edea to Kribi, near the village Koukoue (03°43'18.1'' N, 10°06'26.9'' E), H. Kullmann, B. Misof and R. Sonnenberg leg., collection locality C 01/77.

ZFMK 39965-39969 (4 males, 1 female), Cameroon, a small creek near the road Edea to Kribi (03°36'29.2'' N, 10°06'26.2'' E), H. Kullmann, B. Misof and R. Sonnenberg leg., collection locality C 01/78.

CENAREST, Batoke, Cameroon (1 male, 1 female), same collection data as ZFMK 39960-39964, collection locality C 01/77 .

Diagnosis. Chromaphyosemion koungueense is distinguished from its closest relatives, C. omega sp. nov. and C. punctulatum , by the bluish-green color on side of males and copper-brown metallic scales on dorsal part of sides; with bluish-green to yellow-greenish unpaired fins, on dorsal and caudal fins with red dots or streaks in basal and streaks in distal parts, almost no red patterns on pelvic and anal fins except for small red stripes on fin rays in anal fin in some specimens versus bluish-orange on sides with metallic greenish to copper scales on dorsal sides in combination with mainly orange fins with greenish center in dorsal and caudal and nearly complete orange anal and pelvic fins in C. omega sp. nov. or greenish sides with bluish-green metallic scales on dorsal part of sides, red dots on greenish to yellowish-green anal fin in combination with mainly red dots in dorsal and caudal fin in C. punctulatum . Lateral dark stripes in males more prominent than in C. omega sp. nov. and C. splendopleure s.l. It is distinguished from C. loennbergii by the greenish body color and greenish color of pelvic and anal fins, if yellow to yellow-orange then only in lower half versus metallic copper color on scales on dorsal part of sides and bluish on sides in males, with blue in lower half and orange in upper half of anal fin. It is distinguished from C. melanogaster by the more bluish-green color on side of males together with the orange anterior ventral color of body and orange in caudal and anal fins versus green color on sides and not orange on anterior ventral body, unpaired fins green. The species can be distinguished from C. splendopleure s.l. by the sides being bluish-green with greenish color of anal fin and marginal blue band versus reddish, orange or yellow with bluish or pinkish on sides in adult males, orange or yellowgreenish anal fin with greenish or orange marginal band. It is distinguished by all remaining Chromphyosemion species by the unique combination of color patterns.

Description. See Figures 3-6 for general appearance and Table 2 for morphometric data of the type series. Shows all characters apomorphic for Chromaphyosemion , strong sexual dimorphism, adult males more colorful and usually larger than females and having larger fins with extended fin rays. Slender, laterally slightly rounded and elongate small nothobranchiid species, females anteriorly more rounded than males. Dorsal profile straight on head, from nape to caudal peduncle slightly convex, greatest body height anterior to base of dorsal and anal fin. Ventral profile slightly convex from head to end of anal fin base, caudal peduncle slightly concave on ventral. Snout slightly rounded, mouth directed upwards, lower jaw longer than upper, posterior end of mouth at same level as center of eye. Dorsal and anal fins in males pointed, dorsal fin with elongated fin streamer, anal fin trapezoid, only slightly pointed. Caudal fin in males with middle lobe; elongated fin streamers with same color as in dorsal fin. Fins in females generally smaller and rounded. Unpaired fins usually covered basally with an opaque mucus film. Dorsal and anal fins posterior to mid-body First ray of dorsal fin in front or above 1st or 2nd anal fin ray. Dorsal fin with 11-13 rays, anal fin with 13-14 rays. Pectoral fins extending over origin of pelvic fins, pelvic fins not or just reaching anal fin.

Scales cycloid, body and head entirely scaled, except ventral surface of head. Frontal squamation of G- type, scales on mid-longitudinal series 24-26 + 2-3 on caudal fin base. Transverse row of scales above pelvic fins 8-9, circum-peduncular scale row 12-13. Open frontal neuromast system with two separate grooves, preopercular neuromast system with 6 pores.

Coloration. Live specimens. Males (Figs. 3-5). Back brownish, scale border darker, some with red dots, upper rows of scales on sides from approximately area of greatest body height to end of caudal peduncle reflecting metallic copper to greenish. On sides two parallel black stripes, the upper one starting on lower lip through center of eye straight to dorsal part of caudal peduncle, the lower stripe starting on throat, running directly under eye to ventral part of caudal peduncle, both ending at caudal fin base. Black stripes can completely disappear depending on mood and social status of individual or only traces are seen from upper one on anterior half of body, lower one from anterior base of anal fin to base of caudal fin on ventral caudal peduncle; in fully colored males a dark marking of upper stripe left directly behind opercle. Sides pale grey to beige, many scales with dark border or red dot. Anterior ventral part in males often orange, on lower dark stripe scales with metallic bluish to greenish sheen. In fully colored males, throat and belly at anterior part of body orange, above and on posterior sides metallic bluish-green or greenish, ventrally posterior lower black stripe often visible.

Dorsal fin in center bluish-green or greenish, on anterior part sometimes with copper or orange area, posterior green. On basal part red dots between fin rays, in most specimens fusing to streaks in upper half of fin, fin streamer yellow to orange. Anal fin greenish, on basal part blue in several specimens, submarginal band red, marginal band blue, in central part of anal fin sometimes with a yellowish-green or yellowish-orange area, often restricted between fin rays. Usually without red dots or streaks in anal fin, in some specimens with basal row of red dots. Caudal fin upper and lower margin blue, in lower part with submarginal red band, in upper part blue margin interrupted by red streaks. Fin in center green or bluish-green, in most specimens one not sharply separated yellowish-green to orange band above submarginal red band. Between fin rays red streaks in posterior central part, in anterior part quite variable, varying from red dots to streaks, red pattern ranging between fine to rather broad markings. Orange fin streamers in adult males, in young fish sometimes whitish to yellow. Pelvic fins similarly colored as anal fin, greenish to yellowish-green with red submarginal and blue marginal band. Pectoral fins hyaline with yellow to greenish hue, more intensive on outer fin border. Females (Fig. 6). Back brown, dorsally first three rows of scales with metallic copper or greenish color, similar but less pronounced as in males; scales with dark border, some with red dot, on sides two parallel black stripes, between stripes pale greyish to bluish, ventrally greyish to whitish. Some specimens with small red dots on scales, more or less regularly in rows. Orange area on opercle between lateral stripes. All fins hyaline, coloration similar to fins of males, metallic bluish-greenish. Dark or red dots in dorsal, dots or streaks in caudal fin. Anal fin greenish with dark submarginal region and marginal blue band. Pelvic fins hyaline greenish with bluish margin. Pectoral fins hyaline with little dark pigmentation.

Preserved in ethanol. Males. Back and sides brown, both lateral stripes dark brown, belly light brown to whitish. Scales on back with dark brown border forming reticulated pattern, on back and sides sometimes traces of red on scales. Border of opercle ventral to lower stripe dark, below lower lip whitish to beige. Unpaired and pelvic fins hyaline greyish with dark pigmentation between fin rays, dark margins on unpaired and pelvic fins. Pectoral fins hyaline.

Females. Similar to males and juveniles. Body brownish, scales on back with dark border, belly beige to whitish. Fins hyaline greyish, little dark pigmentation and no dark margin on anal fin.

Etymology. This species is named after the river and the nearby village Koungué, the collection locality of the holotype. With this name, I also want to acknowledge the friendly welcome and invaluable help of the Koungué villagers.

Distribution and habitat. C. koungueense is endemic in Cameroon and known from the area north of Kribi up to Douala at the Wouri (see Map 1). South of the Sanaga it is replaced in the east by C. loennbergii , north of the Sanaga by C. omega sp. nov. and C. riggenbachi . In the northern part of its distribution area it is replaced by C. splendopleure s.l. probably at the Wouri, in the south it is currently not clear if it is in direct contact with C. melanogaster or C. punctulatum . Around Kribi the latter two species are known together with C. loennbergii but the distribution of C. koungueense for this area is unknown in detail.

The type locality is a small river in the forest, about 3 m wide and 0.4 m deep. It has a muddy bottom on sand, covered with decomposing leaves. The water temperature was 26°C, air temperature 28°C, pH 4.9 and conductivity ~10 µS/cm. Syntopic fish species were Epiplatys infrafasciatus , 'Aphyosemion' ahli, Kribia nana , juvenile Benitochromis cf. finleyi and Barboides gracilis .

Remarks. This species is comparatively variable in color patterns compared to C. omega sp. nov. and C. punctulatum as closely related species. Despite this the isolated populations of Bioko and Bimbia (Figs. 7-8) are tentatively excluded here as there are probably significant differences in color patterns, but not as clear as in comparison with C. omega sp. nov. Additionally they are completely allopatric and separated from the distribution area of C. koungueense by the Atlantic Ocean or the Wouri estuary respectively. Instead of the premature inclusion in the latter species, the taxonomic status of these populations should be reconsidered after detailed studies including, e.g., mate-choice experiments.