Saurida lessepsianus Russell, Golani et Tikochinski 2015
Saurida lessepsianus Russell, Golani et Tikochinski, 2015
Figs 2, 3, 4
Description of specimens from west coast of India.
Body elongated and slightly cylindrical; body depth 17.2% of SL; depth of caudal peduncle 6.5% of SL (Table 1); pectoral fins moderately long, reaching or just extending beyond base of pelvic fins; axillary scale long and pointed; dorsal-fin base length comparatively longer than anal-fin base.
In fresh condition, body dark dorsally and light colored below the lateral line with a series of 9 small blotches along the lateral line; 6-10 indistinct black spots on the first two dorsal rays; 6-8 distinct black spots on the dorsal margin of the caudal fin; adipose fin whitish with black blotches anterodorsally; pelvic and anal fin whitish; lower lobe of the caudal fin and upper part of the pectoral fin blackish (Fig. 2); stomach black anteriorly and white posteriorly, with white intestine (Fig. 3).
Counts and proportional measurements of the specimens are provided in Table 1. The mode and range of meristic traits of S. lessepsianus: Dorsal-fin rays 11 (11-12); pelvic-fin rays 9; pectoral-fin rays 14 (13-15); anal-fin rays 11 (11-12); lateral-line scales 49 (48-51); transverse scales above and below lateral line 4½ and 5½, respectively; pre-dorsal scales 15 (15-19); pre-adipose scales 14 (14-16); vertebrae 47 (44-47) (Fig. 4); two rows of palatine teeth; no teeth on vomer; 4-6 tooth rows on tongue.
Around 650 bp of COI gene were amplified and sequenced using primers. The sequence quality was verified by observing the Phred score of each nucleotide using Finchtv software. The sequences were submitted to the GenBank with accession numbers of MN853856 and MT139594-MT139596 (COI). The ends of the COI sequences were trimmed to include all reported sequences which resulted in a sequence length of 544 bp. The genetic distance values found in the presently reported study and reported sequences from India were 0; accordingly, sequences were clustered into a single clade. The mean genetic distance values between S. lessepsianus of the Mediterranean/Red Sea and the Arabian Sea was 0.008 ± 0.002. These sequences formed separate branches of the clade. The mean genetic divergence value between S. lessepsianus and S. undosquamis of Australian waters was 0.079 ± 0.012 (Table 2). The sequences of S. lessepsianus were clustered distinctly from S. undosquamis reported from Australia (Fig. 5).
(Below the diagonal (values in bold): genetic distance values; PS: presently reported study samples; Su1: Reported sequences of Saurida ' Saurida undosquamis ' from India; SLRS: Reported S. lessepsianus from Red Sea / Mediterranean Sea; SUAU: Reported S. undosquamis from Australia). *Only one sequence used for analysis.
Biology. Saurida lessepsianus n. sp. is found mainly on sandy or muddy substrates to about 100 m, 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). 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 * 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.
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 4 ½, below lateral line 5 ½; 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.
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.
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.
Distribution. Red Sea endemic; Mediterranean Sea (Red Sea immigrant). Conservation. IUCN: Global (LC: 28 June 2018). Capture and threats: Unknown. Occurrence: Very common. Non-indigenous species, no conservation action needed.
Introduced species vector dispersal
Cypriote part of the Mediterranean Sea - Eastern Basin (Marine Region) Canals: natural range expansion through man-made canals (Suez Canal)