Lutjanus sapphirolineatus, Iwatsuki, Yukio, Al-Mamry, Juma M. & Heemstra, Phillip C., 2016

Iwatsuki, Yukio, Al-Mamry, Juma M. & Heemstra, Phillip C., 2016, Validity of a blue stripe snapper, Lutjanus octolineatus (Cuvier 1828) and a related species, L. bengalensis (Bloch 1790) with a new species (Pisces; Lutjanidae) from the Arabian Sea, Zootaxa 4098 (3), pp. 511-528 : 523-525

Lutjanus sapphirolineatus n. sp.

Proposed English name: Arabian blue-striped snapper Figures. 2 C, 4; Table 1

? Genyoroge bengalensis ; Günther 1859: 178 (Red Sea).

Lutjanus bengalensis (non Bloch): Dor 1984: 138 (?in part, Red Sea); Allen & Talbot 1985: 21 (in part, Middle East); Allen 1985: 61 (in part, Middle East); Goren & Dor 1994: 37 (?in part, Red Sea); Randall 1995: 197 ( Oman); Manilo & Bogorodsky 2003: S108 (?in part, Red Sea); Heemstra & Heemstra 2004: 201 (?in part, Middle East); Fricke et al. 2009: 60 [?in part, Western Indian Ocean]; Iwatsuki et al. 2013: 32 ( Oman).

Holotype: MUFS 33724, 153 mm SL, Muttra, Gulf of Oman, Oman.

Paratype specimens (n = 9): MUFS 33521‒33522, 2 specimens, 79‒144 mm SL, Muttra, Oman; OMMSFC 760 (formerly MUFS 33723), 145 mm SL, same as holotype SAIAB 201838 (formerly MUFS 33523), 143 mm SL, same as holotype; USNM 305002, 4 specimens, 137‒145 mm SL, Somalia (10°44'30"N, 051°14'30"E).

Diagnosis. A species of Lutjanus with the following combination of characters: Dorsal fin XI, 13; anal fin III, 8; pectoral fin 17; lateral-line scales 47‒49: horizontal scale rows above lateral line 5 or 6; scale rows above lateral line rising obliquely toward dorsal profile; predorsal scales extending forward just above anterior edge of orbit; scale rows on cheek 6 or 7 without subocular extension of smaller scales; subocular extension of cheek scales irregularly present in 1 or 2 row(s) anteriorly and 3 or 4 rows posteriorly below eye, respecitvely; gill-rakers on first arch 8 or 9 + 18 or 19 = 26‒28; tongue smooth, without teeth; preopercular notch developed just above angle; interopercular knob inconspicuous; belly white with yellow spot on each scale forming narrow, longitudinal, yellow lines; four dark-edged blue stripes present, the first blue stripe almost running from above posterior nostril to the tenth dorsal fin spine base; the third just from upper rear edge of eye, through upper part of opercle, tapering posteriorly and extending to upper part of caudal peduncle below last soft dorsal-ray base; fourth blue stripe from just above midpoint of lower jaw, below eye and continuing through opercle, above upper pectoral-fin base to caudal peduncle.

Description. Meristic counts and proportional measurements as percentages of standard length (SL), plus two diagnostic characters in coloration and squamation of subocular extension for the holotype, nine paratype and nontype specimens of Lutjanus sapphirolineatus n. sp. are shown in Table 1. Characters presented in the diagnosis are not repeated.

Body slender and elongate to moderately deep, laterally compressed, greatest depth 2.7 – 3.1 (3.0 in holotype) in SL; head length 2.5‒2.7 (2.7 in holotype) in SL; snout length 3.1‒3.7 (3.6 in holotype), eye diameter 3.3‒3.7 (3.3 in holotype), interorbita1 4.2‒5.1 (4.2 in holotype), maxilla length 2.5‒3.3 (2.5 in holotype), and preorbital depth 6.7‒8.9 (8.5 in holotype), in head length; head small with pointed snout; snout-forehead profile straight; body, opercle and preopercle with finely ctenoid scales; parietal, frontal, interorbital and rear edge of preopercle scaly; pair of small rounded anteriorly and somewhat ovate nostrils posteriorly, respectively, and anterior and posterior openings on each side of snout, with very low flap on outer edge of anterior nostril; vomerine with minute crescentshaped tooth patch without posterior extension; preopercular margin finely serrate (serrae increasing in size ventrally); sharp, flattened, flexible projection at middle of opercular margin, with blunt bony spine (mostly covered by scales) immediately above its base; opercular, interopercular and subopercular margins otherwise smooth; upper jaw with dagger-like short canine on each side anteriorly, a smaller canine between it and symphysis; remaining lateral portion of upper jaw with a series of 8 – 10 smaller canines, lower jaw with 10 – 12 small canines on either side, almost embedded, not visible except anterior canine slightly visible when mouth closed; dorsal-fin margin weakly incised, fourth to fifth spines longest, remaining spines gradually decreasing in length; profile of soft dorsal-fin relatively low and weakly rounded; pectoral fins pointed; caudal fin emarginate.

Color in life, based on photographs (MUFS 33724, 153 mm SL, holotype, photographed by Y. Iwatsuki); G.V. Hermosa, Jr. photograph (http://www.fishbase.org/photos/PicturesSummary.php?StartRow=2&ID=1409&what=s pecies&TotRec=6 [accessed in 18 Dec. 2015] and http://www.fishbase.org/photos/UploadedBy.php?autoctr =7077&win=uploaded [accessed in 18 Dec. 2015], Gulf of Oman): bright yellow on upper half, white ventrally; belly with yellow spot on each scale forming narrow, longitudinal yellow lines; upper body with four dark-edged blue stripes, uppermost extending from interorbital to tenth spinous dorsal fin, second from upper edge of eye to front of soft dorsal-fin base, third from upper rear edge of eye, through upper part of opercle, tapering posteriorly and extending to upper part of caudal peduncle below last soft dorsal-ray base; the fourth stripe beginning from just above midpoint of upper jaw, continuing just beneath eye, over middle opercle, area above upper pectoral fin base, nearly to middle of caudal peduncle just below lateral line; median fins yellow; pectoral and pelvic fins whitish; iris golden yellow.

Color in alcohol: generally yellowish tan (including fins), with four brown or bluish stripes as noted above.

Distribution. Lutjanus sapphirolineatus n. sp. seems to be confined to the Middle East, and is currently known only from Somalia and Oman. However, we guess that this species is likely to be distributed in the southern Red Sea and the Gulf of Aden as well, because Dor (1984, Red Sea) and Randall (1995, Oman), reported L. bengalensis from there. If these reports are accurate, we presume they refer to L. sapphirolineatus n. sp. Manilo & Bogorodsky (2010) included L. bengalensis in their checklist based on specimens collected Karaman Island, Yemen, in southern Red Sea. On request of the first author of this article, specimens deposited in SAIAB collection, were examined and reidentified as L. kasmira (E. Heemstra pers. comm.). Our current distributional information is that L. sapphirolineatus n. sp. might be distributed in southern Red Sea but L. bengalensis is not likely to occur in southern Red Sea although Günther (1859) also reported the name, Genyoroge bengalensis , from Red Sea (this needs further confirmation).

Etymology. The species is named “ sapphirolineatus ” with reference to the diagnostic character of four blue stripes on the body of this species.

Remarks. Lutjanus sapphirolineatus n. sp. from Somalia and Oman has long been confused with L. bengalensis , as noted above, but careful examination of the blue-striped snapper complex from the Indo-Pacific shows that specimens from the Middle East should be considered as new to science. Lutjanus sapphirolineatus n. sp. differs from L. octolineatus and L. bengalensis in having the following combination of characters: a stripe on upper preopercle and upper opercle, continuing as the third blue stripe, 11 dorsal-fin spines, and the presence of a suborbital extension of cheek scales (often as 1‒4 scale row[s] posteriorly); horizontal scale rows above lateral line 5 or 6; vs. the third stripe beginning from rear edge of opercle, 12 dorsal-fin spines, and the presence (1 or 2 scale row[s]) of a suborbital extension of cheek scales (1 or 2 scale row[s]) and 8 or 9 horizontal scale rows in L. octolineatus ; and vs. presence of a blue stripe on upper opercle, 11 dorsal-fin spines, 8 or 9 horizontal scale rows and no anterior suborbital extension of cheek scales in L. bengalensis .

Comparisons. The blue-striped snapper complex includes the following species: Lutjanus bengalensis , L. coeruleolineatus , L. kasmira , L. notatus and L. quinquelineatus ( Allen & Talbot 1985) . Two others are added to the complex in this report: L. octolineatus and L. sapphirolineatus n. sp., bringing the total to seven species from the Indo-Pacific.

Lutjanus kasmira differs from the six other known blue-striped snappers in having four blue stripes on the body and preopercular flange naked or with some embedded scales ( Allen & Talbot 1985). Furthermore, this species often has narrow gray stripes on a white abdomen and dusky upper pectoral fin and snout region ( Allen & Talbot 1985; this study). Lutjanus coeruleolineatus , L. quinquelineatus , and L. notatus can be differentiated from the four other species in having 7 or 8 (rarely 9), 6, and 5 blue stripes on the body, respectively. Such stripes are usually retained in preserved specimens (vs. see diagnosis above at each and Table 1). Lutjanus coeruleolineatus is easily diagnosed from the other six species in having preopercular flange naked and clear black oval spot below junction between spinous and soft dorsal-fin rays as noted in Introduction. Furthermore, L. quinquelineatus and L. notatus resemble each other but can be differentiated in having X, 13–14 (usually 14) and XI or XII, 12−13 (usually 13) in dorsal-fin rays, respectively ( Allen & Talbot 1985; this study).

Figures

FIGURE 2. Squamation of subocular extension of cheek scales: A. Lutjanus octolineatus MNHN 0000 - 7046, holotype of Diacope octovittata, 137 mm SL; B. L. bengalensis, ZMB 303 (lectotype of Holocentrus bengalensis), 94 mm SL; C. L. sapphirolineatus n. sp., MUFS 33724, holotype, 153 mm SL.