Saurida lessepsianus Russell, Golani et Tikochinski, 2015

Silpa, Susanthi, Srihari, Murugesan, Pavan-Kumar, Annam, Roul, Subal K., Russell, Barry C. & Jaiswar, Ashok K., 2021, Mistaken by dots: Revealing the misidentification of Saurida lessepsianus (Actinopterygii: Aulopiformes: Synodontidae) along the west coast of India (eastern Arabian Sea), Acta Ichthyologica et Piscatoria 51 (2), pp. 185-191 : 185

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 ).

Figures

Figure 2. Saurida lessepsianus collected from Arabian Sea, Mumbai coast, India (131.28 mm SL).

Figure 3. Stomach of Saurida lessepsianus.

Figure 4. X-Ray radiograph of Saurida lessepsianus.

Figure 5. Neighbour-joining tree of the genus Saurida constructed using COI gene.