Saurida lessepsianus, Russell, Barry C., Golani, Daniel & Tikochinski, Yaron, 2015

Russell, Barry C., Golani, Daniel & Tikochinski, Yaron, 2015, Saurida lessepsianus a new species of lizardfish (Pisces: Synodontidae) from the Red Sea and Mediterranean Sea, with a key to Saurida species in the Red Sea, Zootaxa 3956 (4), pp. 559-568 : 560-565

Saurida lessepsianus , n. sp.

New English name: Lessepsian lizardfish Figures 1–3 ; Table 1 .

Saurus Badimottah (in part)— Rüppell 1837 (Gulf of Suez); Dor 1984 (Red Sea, name in synonymy of S. tumbil ).

Saurida tumbil (not Bloch, 1795)— Chabanaud 1932 (Grand Lac Amer = Great Bitter Lake, Suez Canal).

Saurida gracilis (not Quoy & Gaimard 1824)— Chabanaud 1934a, 1934b (Lake Timsah, Suez Canal).

Saurida sinaitica (nomen nudum) - Dollfus in Gruvel 1936 (Gulf of Suez); Gruvel & Chabanaud 1937 (Gulf of Suez); Fowler 1956 (Red Sea, name in synonymy of Saurida gracilis ); Dor 1984 (Red Sea, name in synonymy of S. gracilis ).

Saurida undosquamis (not Richardson 1848)— Norman 1939 (Red Sea); Fowler 1956 (Red Sea); Ben-Tuvia 1966 (Red Sea, Mediterranean); Demidov & Viskrebentsev 1970 (Gulf of Suez, Ghardaqa); Bayoumi 1972 (Red Sea); Dor 1984 (Red Sea); Golani 1993 (Red Sea, Mediterranean); Golani & Bogorodsky 2010 (Red Sea).

Saurida grandisquamis (not Günther 1864)— Ben-Tuvia 1953a, 1953b (Mediterranean); Tortonese 1953 (Mediterranean); Oren 1957 (Mediterranean).

Saurida macrolepis (not Tanaka 1917)— Inoue & Nakabo 2006 (Red Sea); Golani & Bogorodsky 2010 (Red Sea); Fishelson et al. 2010, 2011, 2012a, 2012b (Red Sea, Mediterranean).

Saurida sp.— Bogorodsky et al. 2014 (Red Sea, Jizan)

Holotype. HUJ 20397, 186.0 mm SL, Mediterranean Sea, Israel, Ashdod.

Paratypes (37, 108.0– 282.2 mm SL). AMS I.29395-001, 6: 129.9–166.6 mm SL, Mediterranean Sea, Lebanon, St George Bay. HUJ 6416, 159.9 mm SL, Red Sea, Gulf of Aqaba, Israel, Eilat. HUJ 8436, 2:251.2– 247.4 mm SL, Mediterranean Sea, Israel, Ashdod. HUJ 12231, 184.6 mm SL, Mediterranean Sea, Israel, Jaffa. HUJ 19717, 6:135.1–185.0 mm SL, Red Sea, Eritrea. MNHN 1966-0558, 5: 138.3–214.4 mm SL, Red Sea, Gulf of Suez, Egypt, coll. Dollfus. MNHN 1966-0560, 149.0 mm SL, Red Sea, Gulf of Suez, Egypt. MNHN 1966-0561, 161.2 mm SL, Red Sea, Gulf of Suez, Egypt. MNHN 1989-0822, 3:108.0– 214.8 mm SL, Red Sea, Gulf of Suez, Egypt, coll. Dollfus. MNHN 1989-0825, 135.0 mm SL, Red Sea, Gulf of Suez, Egypt, coll. Dollfus. MNHN 1989- 0 828, 152.7 mm SL, Red Sea, Gulf of Suez, Egypt, coll. Dollfus. MNHN 1989-0829, 155.6 mm SL, Red Sea, Gulf of Suez, Egypt, coll. Dollfus. NTM S.17060-001, 5: 154.6–282.2 mm SL, Mediterranean Sea, Israel, Ashdod. SAIAB 42653, 193.7 mm SL, Mediterranean Sea, Israel, Jaffa. SMF 5405, 147.9 mm SL, SMF 5406, 160.5 mm SL, Red Sea, Gulf of Suez.

Non-type material. Red Sea: HUJ 14919, 253 mm SL, Gulf of Aqaba, Dahab; HUJ 19964, 212 mm SL, Dahlak Archipelago, Bulissar I. Mediterranean Sea: HUJ 14907, 3: 50–141 mm SL, HUJ 19866, 5: 120–130 mm SL, Israel, Haifa Bay; HUJ 19847, 4: 140–246 mm SL, HUJ 19850, 3: 93–125 mm SL, Israel, Jaffa; HUJ 19853, 11: 112–134 mm SL, Israel, Ashdod.

Diagnosis. A species of Saurida with the following combination of characters: dorsal fin with 11–12 rays; pectoral fins with 13–15 rays; lateral-line scales 47–51; transverse scale rows above lateral line 4½, below lateral line 5½; pectoral fins moderately long (tip of fin extending to between just before or just beyond a line from origin of pelvic fins to origin of dorsal fin); 2 rows of teeth on outer palatines; 0–2 teeth on vomer; tongue with 3–6 rows of teeth posteriorly; caudal peduncle slightly compressed (depth a little more than width); upper margin of caudal fin with row of 3–8 (usually 6 or 7) distinct blackish spots; stomach pale grey to blackish anteriorly; intestine whitish.

Description. Counts and proportional measurements of the type series are provided in Table 1 . Dorsal-fin rays 12 (11–12); pectoral-fin rays 14 (13–15); pelvic-fin rays 9; anal-fin rays 11 (10–12). Pored lateral-line scales 50 (47–51); transverse scale rows above lateral line 4½, below lateral line 5½; scale rows below lateral line with melanophores 2 (1–3); pre-dorsal scales 19 (14–19); pre-adipose scales 14 (13–16); post-adipose scales 10 (8–10). Vertebrae 47 (44–47).

Body elongate and cylindrical, somewhat depressed on head and slightly compressed on caudal peduncle, the latter with slightly raised lateral-line scales, forming a slight ridge; scales large, cycloid, not very deciduous; scales present on cheek and opercle. Snout somewhat elliptical when viewed from above. Nostrils located about midway between snout tip and anterior margin of orbit; anterior nostrils a little larger than posterior, anterior one with a broad dermal flap on posterior rim. A prominent low bony ridge extending from just behind nostrils to above middle of orbit. Eye circular, directed laterally; covered with fleshy adipose eyelid anteriorly and posteriorly. Interorbital region broad, slightly concave.

Mouth very large, maxilla extending well beyond posterior margin of eye. Teeth on jaws numerous, small, canine-like, generally in four rows, outermost teeth smallest, innermost longest, visible when mouth closed; similar teeth on the palate, tongue and branchial arches; palatine teeth ( Fig. 3 ) in two separate series: outer series long, with teeth in two rows, those anteriorly longer; inner series short, in about 5–6 poorly defined rows; outer palatine series converge anteriorly but separated by vomer which is toothless or bears 1 or 2 teeth; tongue short, spatulate, fleshy, with triangular shaped patch of teeth, in about 3–6 rows posteriorly; lower jaw slightly shorter and fits into groove between teeth at tip of upper jaw; gill rakers absent, branchial arches each with about 4 rows of teeth, those on the inside largest.

Preadipose length 82.1 80.9 ± 1.4 (76.9–83.2) Preanal length 74.9 71.9 ± 1.9 (67.2–77.1) Preanal-fin length 77.5 74.8 ± 2.5 (65.0–79.3) Prepectoral length 26.3 25.7 ± 1.2 (23.4–28.7) Prepelvic length 41.1 38.8 ± 1.6 (35.4–42.6) Head length (HL) 24.5 24.4 ± 1.0 (22.5–26.5) Body depth 16.0 13.3 ± 1.5 (10.4–17.2) Body width 13.9 13.0 ± 1.3 (10.9–15.6) Interpelvic width 9.3 8.4 ± 0.5 (7.6–9.5) Pectoral-fin length 13.2 14.2 ± 1.3 (11.5–17.0) Pelvic-fin length 16.3 16.6 ± 0.8 (14.2–18.6) Length of 2nd dorsal ray damaged 19.8 ± 1.1 (16.0–21.5) Length of last dorsal ray 6.5 5.8 ± 0.5 (4.9–6.9) Length dorsal-fin base 15.4 14.4 ± 1.0 (12.5–16.6) Length of 2nd anal ray 10.3 9.5 ± 0.9 (7.7–11.1) Length of last anal ray 7.2 5.8 ± 1.1 (3.8–10.5) Length of anal-fin base 9.4 10.0 ± 1.2 (5.5–12.4) Length of caudal peduncle 13.9 14.9 ± 1.2 (12.9–18.7) Depth of caudal peduncle 6.5 6.4 ± 0.3 (5.7–7.1) Width of caudal peduncle 6.0 5.0 ± 0.5 (3.6–5.8) Morphometrics (% HL) Mean ± SD (range) Snout length 21.7 22.2 ± 1.2 (19.4–24.4) Eye diameter 21.2 21.4 ± 1.9 (18.4–25.6) Snout width 24.4 25.4 ± 1.7 (22.6–29.3) Interorbital width 17.1 18.2 ± 1.5 (14.5–21.3) Post orbital length 62.2 59.4 ± 1.7 (54.7–63.5) Upper jaw length 66.8 69.1 ± 1.8 (65.3–73.4) Meristics range

Dorsal fin 12 11–12

Pectoral fin 14 13–15

Pelvic fin 9 9

Anal fin 11 10–12

Pored lateral-line scales 50 47–51

......continued on the next page Origin of dorsal fin just posterior to midpoint of distance from snout to adipose fin origin; base of dorsal fin longer than that of anal fin; adipose fin above posterior half of anal fin; anus just anterior to origin of anal fin; pectoral fin moderately long, 13.2% (11.5–17.0%) of SL; tip of fin extending to between just before or just beyond line between origin of pelvic fins and dorsal fin; pectoral and pelvic fins with long and pointed axillary scales of about equal length; caudal fin deeply forked, upper and lower lobes about equal in length.

Peritoneum pale; stomach grey to blackish anteriorly, whitish posteriorly; intestine whitish.

Colour in alcohol ( Fig. 1 ). Brown on back, paler below lateral line, pigment extending to about 2–3 scale rows below lateral line; about 9 indistinct dusky blotches along lateral line; two dusky, slightly oblique, bars on cheek behind eye; upper margin of upper jaw edged with black; pectoral fins dusky over upper two thirds of fin; pelvic fins pale; anal fin pale; dorsal fin light dusky, 4–10 faint dusky spots on first two dorsal rays (indistinct or absent in holotype and some specimens); caudal fin pale, upper margin with 8 (3–8, usually 6 or 7) black spots, lower lobe dusky; adipose fin dusky on anterior margin.

Colour when fresh ( Fig. 2 ). Top of head and back dark brown or coppery brown, some scales narrowly edged with black, forming a variegated pattern; silvery white below lateral line; series of about nine indistinct small brownish blotches along lateral line; dorsal fin pale, 4–10 indistinct blackish spots on first two dorsal rays; adipose fin whitish with blackish blotch anterodorsally; upper margin of caudal fin with 3–8 (usually 6 or 7) distinct blackish spots, posterior edge and lower lobe of caudal fin dusky; upper part of pectoral fin dusky; pelvic fins and anal fin translucent whitish.

Etymology. The specific name lessepsianus is in reference to the distribution of this species in both the Red Sea and eastern Mediterranean Sea, it having migrated from the Red Sea to the Mediterranean via the Suez Canal, a phenomenon known as “Lessepsian migration” (after the French diplomat Ferdinand de Lesseps, who supervised the construction of the Suez Canal). The common name Lessepsian lizardfish is proposed for this species.

Distribution. Saurida lessepsianus n. sp. is widespread in the Red Sea, including the Gulf of Suez where it is very common. The species has also migrated through the Suez Canal, with the first specimens reported (as S. grandisquamis ) off the Mediterranean coast of Israel in December 1952 ( Ben-Tuvia 1953a). It is now widely distributed in the eastern Mediterranean Sea from Libya to the southern Aegean Sea ( Bilecenoğlu et al. 2002; Bilecenoğlu 2010). Some literature records of S. undosquamis from the Western Indian Ocean (e.g. Cressey 1986; Randall 1995) may also refer to S. lessepsianus n. sp., but pending further study of the S. undosquamis group, its distribution outside of the Red Sea remains unconfirmed.

Biology. Saurida lessepsianus n. sp. is found mainly on sandy or muddy substrates to about 100m, but is more common inshore close to islands or coasts in depths of 20–30 m (S. Bogorodsky pers.com.). This species (reported as S. undosquamis ) is important in the trawl fishery of the Gulf of Suez ( El-Halfawy et al. 2007) and the Mediterranean coast of Egypt, where it is in a state of high overfishing and severe overexploitation ( Mahmoud et al. 2014). In the Mediterranean, it was rather uncommon until 1955, when it started to appear in large quantities in bottom trawl catches ( Ben-Yami & Glaser 1974; Bilecenoğlu 2010). Catches have since remained high, with some fluctuations ( Golani 1993). It is an economically important fish in the Mersin and Iskenderun Gulfs, Turkey ( Torcu & Mater 2000; Bilecenoğlu 2010) and is among the most common species caught in the trawl fishery, comprising almost one-third of the commercial trawl catch in the north-eastern Levant ( Cinar et al. 2005).

The spawning season is prolonged and occurs nearly all the year round, with two peaks in December and May in the Gulf of Suez ( El-Halfawy et al. 2007). In the Mediterranean, the spawning season off the coast of Israel lasts from March to December ( Golani 1993), whereas at Iskenderun Bay, Turkey, spawning occurs mainly in two seasons (May-July and September-November) ( İşmen 2003). It is primarily piscivorous ( Golani 1993; Bilecenoğlu, 2010).

Comparisons ( Table 2 ). Saurida lessepsianus n. sp. differs from S. macrolepis by having relatively shorter pectoral fins (11.5–17.0 % SL, mean 14.2%; versus 14.3–18.4 % SL, mean 15.9 % in S. macrolepis ); 3–8 (usually 6 or 7) spots on the upper edge of the caudal fin (versus dots absent or indistinct in S. macrolepis ); and stomach greyish or black anteriorly, intestine pale whitish (versus stomach black anteriorly and intestine black in S. macrolepis ).

* Inoue & Nakabo (2006) give pored lateral-line scales as 49–55, but their specimens appear to comprise more than one species.

Saurida lessepsianus n. sp. can be distinguished from S. undosquamis , sensu stricto, by having larger body scales (47–51 pored lateral-line scales, versus 54–58 in S. undosquamis ); 44–47 vertebrae (versus 52 in S. undosquamis ); 3–6 rows of teeth across the tongue (versus 7–12 in S. undosquamis ); and stomach greyish or black anteriorly, intestine pale whitish (versus stomach and intestine both pale whitish in S. undosquamis ).

Four other species of the genus are known from the Red Sea ( Bogorodsky et al. 2014): S. golanii Russell 2011 , Saurida gracilis ( Quoy & Gaimard 1824) , S. longimanus Norman 1939 and S. tumbil ( Bloch 1795) . Saurida gracilis can be readily distinguished from the other species by having dark bars or spots on all fins; S. golanii and S. tumbil have the outer series of palatine teeth in three rows (vs. outer series in two rows in S. longimanus and S. lessepsianus n. sp.); and S. longimanus has very long pectoral fins, extending well beyond a line between origin of dorsal fin and origin of pelvic fins. A key to the species of Saurida from the Red Sea is provided below.

Figures

FIGURE 1. Saurida lessepsianus n. sp. Holotype, HUJ 20397, 186.0 mm SL, Mediterranean Sea, Israel, Ashdod.

FIGURE 2. Saurida lessepsianus n. sp. Photograph of freshly collected specimen 182 mm SL, Red Sea, Egypt, Suez (specimen lost). Photograph: S. Bogorodsky.

FIGURE 3. Saurida lessepsianus n. sp. Upper jaw showing outer palatines with two rows of teeth anteriorly (a) and inner palatines with 5 – 6 rows of teeth (b). Photograph: S. Bogorodsky.

Tables

TABLE 1. Morphometric and meristic data of the holotype and paratype specimens of Saurida lessepsianus n. sp.

Standard length (mm)	Holotype 186.0	Paratypes 108.0–282.2 (n = 37)
Morphometrics (%SL)		Mean ± SD (range)
Predorsal length	42.3	42.6 ± 1.2 (40.3–45.0)

TABLE 2. Comparison of selected meristic and morphometric characters for Saurida lessepsianus n. sp., S. macrolepis and S. undosquamis. Pectoral fin lengths are shown as mean ± standard deviation (range) as % SL.

	Saurida lessepsianus n. sp. S. macrolepis (Red Sea-Mediterranean, (Japan, n = 28) n = 38)	S. undosquamis (North-western Australia, n = 22)
Pectoral fin length (% SL)	14.2 ± 1.3 (11.5–17.0) 15.9 ± 1.0 (14.3–18.4)	13.0 ± 1.1 (10.9–15.1)
Pored lateral-line scales	47–51 48–52	54–58*
Vertebrae	44–47 45–57	52
Rows of teeth on tongue	3–6 0–4	7–12
Number of spots on upper margin of caudal fin	3–8 (usually 6 or 7) absent or indistinct	5–12
Colour of alimentary tract	Stomach greyish or black Stomach black anteriorly; anteriorly; intestine pale intestine black whitish	Stomach and intestine pale whitish