Serranus (Paracentropristis) heterurus Cadenat, 1937

Iwamoto, Tomio & Wirtz, Peter, 2018, A Synopsis of the Eastern and Central Atlantic Combers of the Genus Serranus (Teleostei: Scorpaeniformes: Serranidae), Proceedings of the California Academy of Sciences 65 (1), pp. 1-39 : 15-18

Serranus (Paracentropristis) heterurus Cadenat, 1937

Figures 11–12

Paracentropristis heterurus Cadenat, 1937:456–457 , figs 13–14 ( Guinea; 38-65 m). Cadenat and Marchal 1963:1274 ( S. sanctaehelenae distinguished from S. heterurus ).

Serranus heterurus : Heemstra and Anderson 2016:2411(in part; descr. and fig. of S. inexpectatus n.sp.; coast of Guinea to Congo; 25–30 m). Wirtz and Iwamoto 2016: figs 12–15 (comparison with S. pulcher ; specimens from Senegal, Cape Verde Is., São Tomé I, and Guinea)

DIAGNOSIS.— D X,12; P 14–15 (rarely 17), usually 14; A III,7; gill rakers 6-8+15–17 (21–25 total); pored lateral-line scales 45–47; circumpeduncular scales 19–23; scales below origin of first dorsal fin 5–6. Caudal fin truncate, the upper lobe slightly pointed and produced, lower lobe round- ed. Anterior nostril tubelike with high fringed posterior flap. Interradial membranes of dorsal and anal fins scaled on basal one-half to one-third. Nape, opercle, preopercle, pectoral-fin base and chest scaled. Ground color dark red to reddish-orange with seven white vertical bands on body alternating with broad red bands or blocks. A prominent white or blue crescent mark behind orbit in life (dark in preserved specimens); small blue spots ventrally on snout, suborbital and upper lip, and blue to white diagonal streaks on lower part of operculum.

DESCRIPTION.— Body relatively slender and compressed, width over pectoral bases about half of HL, greatest body depth 2.5–3.0 in SL, slightly less than HL, which is about 2.5– 2.6 in SL. Dorsal and ventral profiles gently curved from tip of snout to caudal fin. Snout about equal in length to orbit diameter; both somewhat greater than interorbital width. Lower jaw projecting slightly beyond upper jaw; maxilla extending to below midorbit. Anterior nostril with raised rim, posteriorly rising to a high narrow flap with 2–4 long fingerlike papillae or slender cirri at distal tip; posterior nostril lacking raised rim. Opercular spines three, the uppermost poorly developed and obscure, middle spine longest, the lowermost smaller. Preopercle margin serrated with flattened spines, those at angle largest.

Premaxillary teeth in narrow band, the outer series spaced and slightly enlarged; one or more large canines at anterior end. Dentary with a spaced series of slightly enlarged outer teeth flanking band of much smaller teeth, the tooth series becoming larger posteriorly to near end of gape. Vomerine teeth in broad V-shaped band, followed on each arm by a narrow band of small palatine teeth.

Scales cover most of head, body, and basal parts of dorsal, anal, caudal, and pectoral fins, but absent on the following: snout; on dorsal surfaces of head to front of nape; over suborbital region to above hind margin of maxilla; on jaws; along narrow border behind orbits; on gular and branchiostegal membranes; on entire exposed surfaces of interopercle; and along outer margin of preopercle.

First four to six spines of dorsal fin graduated, the 5 th to 6 th spines longest, the spines following subequal; the soft rays slightly higher than longest spines, the 4 th or 5 th ray longest; a slight notch in fin profile. Anal fin relatively high, its posterior tip rounded; spines shorter than soft rays, the first spine more than half length of second and third spines, the second spine longer and stouter than the others; the anterior and middle soft rays longest. Pectoral fin broad-based, its origin about on same vertical as that of dorsal fin and slightly behind that of pelvic fin; the posterior tips of pectoral and pelvic fins fall short of anus. Caudal fin truncate to somewhat emarginate; dorsal lobe slightly pointed, ventral lobe rounded at tip.

Color: In a live individual from the Cape Verde Islands ( Fig. 11 ), ground color dark wine-red, five broad red bands across body from caudal peduncle to (and touching) base of pectoral fin, another over nape and onto opercle; forward of that a narrower band on preopercle; seven narrow white bands interspersed between red bands of head and body; behind posterior rim of orbit a prominent narrow blue to white crescent-shaped mark; small blue spots cover head and vertical fins. In a fish from Guinea (CAS 234558) ( Fig. 12 ), ground color light reddish-orange, dorsum somewhat darker, snout darkest; five broad dark vertical bands on body, each extending almost entire depth of body, with the exception of the anterior two which fade into white of belly; dark bands alternate with six pale narrower bands, the last dark band narrowest and on caudal peduncle, followed by narrow pale band at base of caudal fin. Two white streaks on cheek from lower part of preopercle extending diagonally downward to interopercle; a light blue crescent mark along hind border of orbit; small blue spots on head and vertical fins. Soft rays of dorsal and anal fins distally dark with trace of blue and speckled with small yellow to gold spots; posterior margins of dorsal and anal fins blackish. Caudal fin with narrow yellowish bands; upper and lower margins yellow; traces of reddish splotches near base of fin. Pectoral fin clear reddish-orange; pelvic fins blackish distally.

Size: 10 cm TL.

HABITAT AND DISTRIBUTION.— On rocky and marl bottoms in 20–65 m. A single specimen from Guinea ( CAS 234558 ) was found amongst a large catch of pen shells, Pinnidae . Senegal, Guinea-Bissau, Guinea, Sierra Leone, Ghana, Cape Verde Islands and São Tomé Island.

REMARKS AND COMPARISONS.— Serranus heterurus has been confused with S. sanctaehelenae , with which it has sometimes been synonymized (e.g., Robins and Starck 1961: 290; Smith 1981:5; 1990:706). Serranus heterurus can be readily distinguished from S. sanctaehelenae by its much smaller adult size (10 cm TL cf. 24 cm), and the following characters that are lacking in S. sanctaehelenae : color pattern (crescent-shaped marking behind orbit; blue spots below orbit; ground color reddish to orange); presence of cirri or fringes on posterior rim of nostril; dorsal lobe of caudal fin slightly produced. Serranus heterurus and the closely related S. pulcher are similar in most meristic and morphometric values, but differ notably in color pattern: S. pulcher is usually an overall dark grey on the upper half of head, the lower part reddish, then white on the underside, broken by a moustache-like marking from upper jaw that tapers medially, the markings on each side almost meeting at interopercles; the white chest is marked by a red streak originating at angle of operculum and ending at origin of pelvic fins; no black spot or margin in dorsal fin; no dark spots or whitish crescent marks on head; pelvic fins usually completely white. A common color variant in São Tomé has broad orange to reddish stripes on body, one dorsally from nape to dorsal margin of caudal peduncle, a midlateral stripe from eye to center of caudal fin base, a third from lower part of head to ventral margin of caudal peduncle; juveniles of this variant may have midlateral and lower stripes black. Comparison of S. heterurus and S. inexpectatus are given in the description of the latter species.

We found much variability in the color patterns, markings, and shape in this species that has led to much confusion as to what species we are dealing with. The original description and illustration of the species by Cadenat (1937) clearly distinguish most specimens from the Cape Verde Islands, Senegal, São Tomé I., Príncipe I., and Guinea.

DNA evidence provided by Benjamin Victor suggests that S. inexpectatus is most closely relat- ed to S. pulcher and together they form a clade that is sister to S. heterurus . Victor’s DNA sequences for S. heterurus came from specimens collected in the Cape Verde Islands; those for S. inexpectatus from Angola, Sierra Leone, and Senegal. We have not had the opportunity to examine the voucher specimens.

SPECIMENS EXAMINED (12 spec.).— Guinea : CAS 234712 (64.8 mm SL) ; 9°24.8ʹN, 14°36.6ʹW; 47–53 m; R/V Dr Fridtjof Nansen [ DFN] CCLME Survey 2012, sta. 7; 11 May 2012 . CAS 234711 (80.8 mm SL) ; 9°46ʹN, 14°46.1ʹW; 34– 33 m; R/ V DFN CCLME Survey 2012, sta. 16; 12 May 2012 . CAS 234558 (73.2 mm SL) ; 10°03.7ʹN, 15°28.5ʹW; 28–29 m; R/ V DFN CCLME Survey 2012, sta. 27; 14 May 2012 . CAS 234709 (46.6 mm SL) ; 10.152°N, 15.9284°W; 35 m; R/ V DFN CCLME Survey 2012; 14 May 2012. São Tomé e Príncipe : CAS 231614 (58.2 mm SL) ; São Tomé Island ; 0°04.35ʹN, 6°38.77ʹE; 56–60 m ; R/ V DFN Survey 2010-04-05, sta. 23; 15 May 2010 . CAS 231627 (66.8 mm SL) ; São Tomé Island ; 65– 55 m ; R/ V DFN Survey 2010-04-05, sta. 32; 18 May 2010. Cape Verde Islands : USNM 405101 (88.3 mm SL) ; 15°45ʹ12ʺN, 23°05ʹ27ʺW; 73– 61m; R/ V DFN Cape Verde 2011 Exped , sta. 10, coll. K. Wieber, 10 June 2011 . USNM 405105 (75 mm SL) , between Santiago and Boa Vista islands; 15°40ʹ06ʺN, 23°11ʹ15ʺW; 77–79 m ; R/ V DFN Cape Verde 2011 Exped , sta. 12, 10 June 2011 . USNM 405181 (69 mm SL) ; 16°34ʹ36ʺN, 23°51ʹ24ʺW; 31–45 m; Cape Verde 2011 Exped., DFN sta. 28, coll. K. Wieber, 14 June 2011 . ZSM 44703 (78.3 mm SL) , ZSM 43730 (39.4 mm SL) , ZSM 43051 (36.0 mm SL) ; Kingfisher Bay at Terrafal on Santiago I.; 15.275522°N, 23.459545°W; 19 m; coll. P. Wirtz, Oct. 2015 .

Figures

FIGURE11. Serranus heterurus. From Tarrafal, Santiago, Cape Verde Islands. Photograph by Patrick Louisy.

FIGURE 12. Serranus heterurus. CAS 234558 (73.2 mm SL) from Guinea in 28–29 m, R/V Dr. Fridtjof Nansen station. Photograph by T. Iwamoto.