Three new endemic Aphyosemion species (Cyprinodontiformes: Nothobranchiidae) from the Massif du Chaillu in the upper Louessé River system, Republic of the Congo Van Der Zee, Jouke R. Walsh, Gina Boukaka Mikembi, Valdie N. Jonker, Michiel N. Alexandre, Marco P. Sonnenberg, Rainer Zootaxa 2018 2018-01-03 4369 1 63 92 Van Der Zee & Walsh & Boukaka Mikembi & Jonker & Alexandre & Sonnenberg, 2018 Van Der Zee & Walsh & Boukaka Mikembi & Jonker & Alexandre & Sonnenberg 2018 [151,481,1455,1481] Actinopterygii Nothobranchiidae Aphyosemion GBIF Animalia Cyprinodontiformes 9 72 Chordata species cyanoflavum sp. nov.     Holotype. AMNH 263406, male, 27.8 mmSL, Republic of the Congo, 1.5 kmsouth of the village of Lisoukou( 10 kmsouth of Mayoko) on the road R1 to Mossendjo, Leyou River, tributary of the Mandoro River, tributary of the Louessé River, Niari Riverdrainage ( 2°21'57" S, 12°46’16" E), field code M27, field label M275, collected by G. Walsh, M. Alexandre& V. Boukaka Mikembi,  22 October 2013.  Paratypes.AMNH 262589, 2 males, 25.5–28.0 mm,  1 juvenilemale, 20.7 mmSL, not measured, Republic of the Congo, collected with the holotype.   Diagnosis.‘  Aphyosemion’  cyanoflavum( Figs 6–9, Table 4) is a member of the ‘ A’. ogoensegroup based on DNA analysis. It can be distinguished from all other  Aphyosemion s.l.species by its cephalic lateral line system, having unique large, dark coloured anterior supra-orbital neuromasts in very wide supra-orbital grooves (18.3–19.4 % of inter-orbital width versus 7.3–16.9 % in other species, Fig. 8, Table 5), very large pre- and postorbital canals with large pores ( Fig. 7) and frontal neuromasts housed in one pit with one anterior lobe; by its wide upper jaw (due to enlarged lacrimal bones), wider than inter-orbital distance versus narrower in all other species, making the dorsal and lateral view of the head much more reminiscent of an  Epiplatys Gill, 1862than an  Aphyosemion s.l.( Figs 7–8). Males are distinguished from all other  Aphyosemion s.l.species by their unique lateral colour pattern: anterior part of body on side yellow and posterior side of body purple-grey. The transition between yellow and purple-grey is very sharp and situated just behind the pelvic fin ( Fig. 9). Males are distinguished from all other members of the ‘ A’. ogoensegroup (except for ‘ A’. caudofasciatum Huber & Radda, 1979, ‘ A’. pyrophore,and ‘ A’.  thysi) by the presence of narrow dark red bars in the posterior part of the flanks and on the caudal peduncle. Males are distinguished from the latter three species by the above mentioned wide supra-orbital grooves and the unique colour pattern of anterior yellow and posterior purple grey on the flanks.   Description.See Figs 6& 9for general appearance and colour pattern, Table 4for morphometric data of types. Medium sized  Aphyosemion s.l.species, largest observed specimen in typeseries 35.5 mmtotal length. Dorsal and ventral profile slightly convex, greatest body depth approximately at base of pelvic fin, ventral profile slightly convex, caudal peduncle dorsally and ventrally concave. Mouth directed upwards, lower jaw longer then upper jaw, upper jaw wider than inter-orbital distance. Frontal neuromasts in one groove with one central anterior lobe, pre-opercular, pre- and postorbital cephalic lateral line system with prominent tubular canals with large pores ( Fig.7). Two supra-orbital grooves with three neuromasts each. Grooves wider and deeper than in other  Aphyosemion s.l.species ( Table 5). Anterior part of supraorbital groove strongly widened with many melanophores ( Figs 7& 8). Anterior-most supra-orbital neuromasts large and dark grey to black due to dense concentration of melanophores ( Fig. 7). Dermal lobes bordering the grooves very small, shallow and narrow. Teeth on jaws unicuspid, outer row large and inward curved, inner teeth smaller and more irregularly placed. Scales cycloid, body completely scaled except ventral head surface. Frontal squamation variable, one specimen of G-type, one specimen of E-type (third specimen lost its G- and E-scales). G-scale narrow and elongated due to wide supra-orbital grooves. Two F-scales present ( Fig. 8). Noscales on dorsal and anal fin base. Caudal fin base with two to three scale rows. Scales in mid longitudinal series 29–30, transverse series of scales before dorsal fin nine, circumpeduncular scale row 14. All unpaired fins pointed in males. Number of dorsal fin rays 11–12, anal fin rays 14–15; first dorsal fin ray above anal fin ray seven to eight. Pectoral fin not reaching pelvic fin, pelvic fin just reaching anal fin.  Live colouration. Males ( Fig. 9). Snout dark grey to black. Eye iris light with some metallic green areas on outer margin. Three red streaks on opercle in approximate 45° angle, top red streak behind eye can be reduced to red spot, lower red streak short or reduced to red spot at the posterior tip of the operculum. Anterior part of body yellow with green iridescence, posterior part purple grey, metallic ice blue iridescence, anteriorly in patches, otherwise concentrated at scale border. Most scales on upper half of anterior side of body with small red rounded spot forming up to four irregular horizontal lines, lower being very short. Lower half of anterior body without or with sparse red spots. Majority of scales on posterior part of body with variable larger dark red spots, forming irregular bars. Body dorsally brownish, ventrally from chin to halfway between pelvic and anal fin bright yellow. Unpaired fins light blue with metallic sheen and dark black or red margin (narrow in anal fin and broad in caudal and dorsal fin), dark red dots and/or short streaks between fin rays. On caudal fin two larger dark red dots at centre of fin base and one large red dot at the ventral caudal fin base. Pelvic fin light metallic blue, sometimes with few red spots. Pectoral fin hyaline with blue metallic margin.   TABLE 4.Morphometric and meristic data of ‘ A’.  cyanoflavum, new species. Abbreviations: TL = total length, SL = standard length, HL = head length, BD = body depth, E = eye diameter, IO= inter-orbital distance, pD = pre-dorsal length, pA = pre-anal length, CL = caudal peduncle length, CD = caudal peduncle depth, CL/D = caudal peduncle length/ depth ratio, DB = dorsal fin base, AB = anal fin base, 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, C = number of caudal fin rays, P = number of pectoralfin rays, LLS = number of scales on the lateral line, TS = number of transversal scales on one flank, CS = number of scales around the caudal peduncle. SL is given in mm, other measurements as percentages of SL, sd = standard deviation.    Holotype Male Paratype range (2 males) Mean all types (sd)  TL 127.7 126.2 – 127.9 127.3 (0.9)  SL 27.8 25.5 – 28.0 27.1 (1.4)  HL 28.4 27.5 – 27.9 27.9 (0.5)  BD 20.9 19.6 – 20.4 20.3 (0.7)  E 9.4 8.6 – 9.0 9.0 (0.4)  IO 12.2 11.4 – 11.8 11/8 (0.4)  pD 68.0 64.7 – 67.5 66.7 (1.8)  pA 62.2 61.4 – 62.4 62.0 (0.5)  CL 26.3 24.7 – 26.1 25.7 (0.9)  CD 12.2 11.4 – 12.9 12.2 (0.8)  CL/D 2.2 2.0 – 2.2 2.1 (0.1)  DB 15.8 14.5 – 16.4 15.6 (1.0)  AB 18.7 18.4 – 18.9 18.7 (0.3)  D 12 11 11.3 (0.6)  A 15 14 – 15 14.7 (0.6)  D/A 8 7 – 8 27.7 (0.6)  C 26 26 26(0)  P 14 14 – 15 14.7 (0.6)  LLS 29 29 – 30 29.7 (0.6)  TS 9 9 9 (0)  CS 14 14 14 (0)  After 3 months in 70 % ethanol. ( Fig. 6). Lower lip black to dark grey. Operculum and head below eyes light grey, red streaks on operculum as in live specimens. Flanks grey with sharp transition to unpigmented whitish ventral side anterior of pelvic fin. Large dark grey to black blotch on anterior flank. Melanophores of posterior flank scales concentrated on posterior margin of scale. Dorsal third of body with irregular lines of red spots. Dorsal, anal, and caudal fins light grey, with irregular red dots and streaks between fin rays, and with narrow dark margins as in live specimens. Pelvic and pectoral fins light grey at base and dark grey at margin.   Distribution and habitat.‘  Aphyosemion’  cyanoflavumis currently only known from the typelocality in the southern Massif du Chaillu. The Leyou River is a small stream flowing into the upper Mandoro River, a tributary of the Louessé River in the south-western part of the Republic of the Congo. It is found syntopic with ‘ A’.  coelesteand ‘ A’.  mandoroense, new species, where they occur in more or less similar microhabitats. ‘  Aphyosemion’  cyanoflavumseems to be rare in the study area. Although the area was thoroughly sampled by four of the authors (GW, MA, MJ & VBM) during two field seasons and many  Aphyosemion. s.l. specimens were collected; it was only present at the typelocality in the upper Mandoro River system. It cannot be excluded that it occurs in rivers east of the Mandoro, since no fish collections were made there.   Etymology.The name  cyanoflavumrefers to the bicoloured flanks in live males, the anterior part of the body being yellow (Latin: flavum, meaning yellow an adjective) and the posterior part predominantly blue ( cyanofor the Greek kýanos, meaning blue, an adjective).   TABLE 5.Relative width of supra-orbital groove of cephalic sensory system (width groove in percentage of inter-orbital distance) and relative width of G-scale (width of G-scale in percentage of length of G-scale).    Taxon Relative width groove Relative width G scale  ‘ A’.  cyanoflavum 18.3–19.4 59.5–68.4  ‘ A’. ogoensegroup * 11.3–14.1 87.2–104.8  ‘ A’.  mandoroense 13.9–15.0 67.6–75.5  ‘ A’. ocellatum 15.9–16.9 57.5–76.2  ‘ A’.  coelestegroup ** 10.1–13.1 85.8–118.3  ‘ A’. punctatumgroup 9.9–11.4 130.3–135.3  ‘ A’. herzogigroup 10.5–11.6 109.1–123.4    Aphyosemion 10.3–10.6 111.7–117.0    Chromaphyosemion 8.5–12.1 116.5–139.9    Diapteron 7.3–9.4 114.5– 123.7    Episemion 14.9–15.5 51.5–54.9   Iconisemion 9.9–11.1 106.1–116.9    Kathetys 9.7–13.4 95.1–110.1    Mesoaphyosemion 10.3–11.0 91.6–93.3    Raddaella 10.0–12.2 89.7–113.5   Scheelsemion 10.1–10.8 114.3–134.4  ‘ A’.  hera 9.2–9.3 118.0–148.6  ‘ A’. hofmanni 14.2–16.9 104.9–117.2  ‘ A’.  tirbaki 12.6 106.9  ‘ A’. wachtersi 11.8–11.9 77.6 –95.2 * except ‘ A’.  cyanoflavum ** except ‘ A’.  mandoroenseand ‘ A’. ocellatum 1802482618 2013-10-22 AMNH G. Walsh & Alexandre & Boukaka Mikembi Republic of the Congo Lisoukou -2.3658333 Mossendjo 21 12.771111 Mayoko 9 72 AMNH 263406 1 holotype 1802482611 Republic of the Congo Republic of the Congo 9 72 1 1 holotype