Sphyraena helleri Jenkins, 1901

Morishita, Satoshi & Motomura, Hiroyuki, 2020, Sphyraena stellata, anew barracudafromthe Indo-Pacific, with redescriptionsofS. helleri Jenkins, 1901 and S. novaehollandiae Günther, 1860 (Perciformes: Sphyraenidae), Zootaxa 4772 (3), pp. 545-566 : 546-547

Sphyraena helleri Jenkins, 1901

[English name: Heller’s Barracuda]

( Figures 1 , 2A , 3 , 4 , 10 , 11 A , D–F, 12; Tables 1, 2)

Sphyraena helleri Jenkins, 1901: 387 , fig. 1 (type locality: Honolulu , Oahu Island, Hawaiian Islands).

Holotype. USNM 49692, 315.4 mm SL, Honolulu , Oahu Island, Hawaiian Islands.

Non-type specimens. 3 specimens, 243.3–545.8 mm SL, all from Hawaiian Islands . BPBM 8787, 545.8 mm SL, obtained from fish market in Honolulu, Oahu Island, J.E. Randall and H.A. Randall, 4 Nov. 1969 ; BPBM 24426 , 268.0 mm SL, off Haleiwa , northwest side of Oahu Island, 21°40′00′′N, 158°07′01′′W, shrimp trawl, 3 Dec. 1968 ; BPBM 24400, 243.3 mm SL, off Haleiwa , northwest side of Oahu Island, 21°37′00′′N, 158°10′01′′W, shrimp trawl, P. Struhsaker et al., 30 Nov. 1968 .

Diagnosis. A species of Sphyraena ( Fig. 1 ) characterized by the following combination of characters: one gill raker on first gill arch; pelvic-fin insertion located slightly before vertical through first dorsal-fin origin; pored lateral-line scales 121–127, total lateral-line scales 132–134; scales above and below lateral line 12 or 13 and 14 or 15, respectively; snout comparatively long, its length 15.0–16.4% SL; upper jaw long, its posterior tip reaching to or beyond anterior nostril, but not reaching to below posterior nostril ( Fig. 2A ), its length 11.9–12.9% SL; eye large, orbit diameter and depth 4.8–5.9% and 4.8–5.6% SL, respectively; anal-fin base shortish, its length 6.8–7.5% SL; last dorsal- and anal-fin ray lengths 4.2–4.3% and 3.6–4.7% SL, respectively; anus comparatively close to anal-fin origin, anterior and posterior margins of anus to anal-fin origin 6.5–8.2% and 4.1–4.9% HL, respectively; head sensory canal pores on suborbital area simple or sometimes slightly branched, their lowermost parts very close to lacrimal bone margin, large smooth area lacking canal pores absent on mid-margin of lacrimal bone ( Figs. 2A , 3 ); lateral surface of body without stripes or bands; caudal fin gray.

Description. Counts and proportional measurements as percentages of SL are given in Table 1. Body elongate, cylindrical, moderately compressed anteriorly, progressively more compressed posteriorly. Dorsal profile rising slightly from snout tip to first dorsal-fin origin, horizontal to second dorsal-fin origin, thereafter gently lowering to caudal-fin base. Ventral profile of head and body lowering from lower-jaw tip to pelvic-fin insertion, almost parallel to body axis from pelvic-fin insertion to anal-fin origin, thereafter rising to lowermost point of caudal-fin base. Second dorsal-fin origin just above anal-fin origin. Head large, conical. Eye and pupil, round, lateral on head; orbit elliptical. Nostrils close to each other, located anterior to orbit. Anterior nostril rounded, located slightly below uppermost point of orbit. Posterior nostril semicircular, short flap on anterior edge. Lower jaw longer than upper jaw. Upper jaw long, posterior tip reaching beyond anterior nostril, not reaching to posterior nostril (posterior tip just reaching to anterior nostril in BPBM 24426). Upper jaw with a single row of numerous small straight teeth; 2 pairs of large, recurved, caniniform teeth on symphysis of premaxillary, anterior pair shorter than posterior pair. Lower jaw with a single row of spaced teeth, several anterior teeth smaller; a single large, slightly recurved, caniniform tooth on symphysis of dentary; all jaw teeth ankylotic. Palatine with a single row of irregularly sized caniniform teeth. Vomer toothless. Posterior opercular margin rounded, located anterior to uppermost point of pectoral-fin insertion. Branchial membrane on each side joined distally. Pectoral-fin insertion slightly below lateral-median line of body; posterior tip pointed, not reaching vertical line through pelvic-fin insertion; uppermost ray short, rudimentary. First spine of first dorsal fin longest (second spine in some specimens), last spine shortest and joined to dorsum by fin membrane. Second dorsal fin somewhat falcate, anterior margin rising from fin origin to posterior tip of second fin ray, distal margin concave; first ray unbranched, other rays branched; last ray elongated. Posterior tip of depressed pelvic fin extending to vertical through last spine origin of first dorsal fin; all pelvic-fin rays branched, first ray longest. Anus oval, long longitudinally, positioned slightly before anal-fin origin. Anal fin somewhat falcate, anterior margin lowering from fin origin to posterior tip of second fin ray, distal margin concave; first spine of anal fin short, rudimentary; first ray unbranched, other rays branched; last ray elongated. Caudal peduncle compressed. Caudal fin forked, without a pair of small lobes on central margin. Lateral line continuous, slightly downward from uppermost point of opercle to just above end of anal-fin base, thereafter parallel to body axis. Body, including ventral surface from isthmus to anal-fin origin and pectoral-fin base, covered with cycloid scales. Anterior half of head without scales, except for opercular area covered with small cycloid scales and mandible with row of 4–6 embedded scales. Pelvic and anal fins and axillary region of pectoral fin lacking scales. Upper and lower gill arches with rough platelets; single gill raker long, slender and rough. Opercular gills present. Swimbladder present.

Coloration when fresh (based on USNM FIN 34410) ( Fig. 1A ): Head and body dorsally blackish-silver, ventrally whitish-silver. Lateral body surface without stripes or bands. Pupil black. Pectoral fin darkish transparent. Spines and rays of first and second dorsal fins blackish-gray; membrane darkish translucent. Spines and rays of pelvic and anal fins white, membrane whitish translucent. Caudal fin gray.

Coloration in alcohol ( Figs. 1 B–D). Body slight darkish brown dorsally, elsewhere pale brown. All spines and rays milky white.

Distribution. Endemic to the Hawaiian Islands. Currently known only from Oahu Island ( Fig. 4 ).

Remarks. Sphyraena helleri was originally described by Jenkins (1901) on the basis of a single specimen, collected from the Hawaiian Islands. Although S. helleri has previously been recorded from a wide area in the Pacific Ocean, ranging from southern Japan to Australia, and the East Indies to Easter Island ( Senou 2001; Randall 2007), we determined that the true S. helleri is probably restricted to the Hawaiian Islands.

According to the specimen labels, two small S. helleri , BPBM 24426, 268.0 mm SL and BPBM 24400, 243.3 mm SL, were collected by shrimp trawl at depths of 102 m and 101.5 m, respectively. However, the species is unlikely to inhabit such depths, the specimens having been most likely collected during net hauling.

Figures

FIGURE 1. Fresh (A) and preserved (B–D) specimens of Sphyraena helleri collected from Oahu Island, Hawaiian Islands. (A) USNM FIN 34410, 520 mm SL, specimen not retained, photo by J. Randall; (B) BPBM 8787, 545.8 mm SL; (C) BPBM 24426, 268.0 mm SL; and (D) USNM 49692, holotype, 315.4 mm SL.

FIGURE 2. Illustrations of head showing sensory canal pores of (A) Sphyraena helleri, BPBM 8787, 545.8 mm SL, Oahu Island, Hawaiian Islands, (B) S. novaehollandiae, NSMT-P 112435, 598.0 mm SL, south coast of Australia, and (C) S. stellata n. sp., KAUM–I. 122319, holotype, 430.7 mm SL, Okinoerabu-jima island, Amami Islands, Japan. Area indicated by broken red line indicates absence of sensory canals. Closed and open triangles indicate anterior and posterior nostrils, respectively.

FIGURE 3. Cyanine Blue stained heads of Sphyraena helleri showing sensory canal pores. (A) entire head of BPBM 8787, 545.8 mm SL; (B and C) suborbital regions of BPBM 24400, 243.3 mm SL and BPBM 24426, 268.0 mm SL, respectively.

FIGURE 4. Distributional map of Sphyraena helleri (yellow stars), S. novaehollandiae (blue squares), and S. stellata n. sp. (red circles). Closed and open symbols indicate records based on specimens examined in present study and literature records, respectively.

FIGURE 10. Relationships of (A) snout length, (B and C) orbit diameter and depth, respectively, and (D) upper-jaw length (as % of SL) to SL (mm) in Sphyraena helleri (yellow stars), S. novaehollandiae (blue squares), and S. stellata n. sp. (red circles). Arrowheads indicate holotypes.

FIGURE 11. Ventral views of anus and anal-fin origin of (A) Sphyraena helleri, BPBM 8787, 545.8 mm SL, Oahu Island, Hawaiian Islands; (B) S. novaehollandiae, NSMT-P 112435, 598.0 mm SL, south coast of Australia; and (C) S. stellata n. sp., BPBM 16600, 587.0 mm SL, Pitcairn Islands. Red, blue, and black arrows indicate anterior and posterior margins of anus, and anal-fin origin, respectively. D, E and F show relationships of anal-fin base length (as % of SL), and AMA and PMA to anal-fin origin, respectively (as % of HL) to SL (mm), in S. helleri (yellow stars), S. novaehollandiae (blue squares), and S. stellata n. sp. (red circles). Arrowheads indicate holotypes.