Description of the post-larvae and juveniles of Scomberomorus lineolatus (Cuvier & Valenciennes, 1831) from Indian waters

Summary

Five early ontogenic stages of Scomberomorus lineolatus (C. & V.) ranging in standard length from 18·4 mm to 99·5 mm are described.

Direct comparison of these early stages with those of S. commerson (Lac.) showed differences in the number of gill rakers, the length of preopercular spines and the position of the anal fin in relation to the second dorsal fin. In the case of S. guttatus (Bl. & Schn.) the gill rakers are of the same number as in S. lineolatus but the preopercular spines decrease in size from above with the upper two subequal in size and none projects beyond the operculum.

In the earlier stages, S. lineolatus could be easily distinguished from S. guttatus by the absence of the bluish green coloration characteristic of S. guttatus. In later stages when the coloration has developed in both the species the only marked difference between the two is in the nature of the bent portion of the lateral line which is wavy in S. lineolatus and straight in S. guttatus.

The number of vertebrae is 46 in S. lineolatus; 42–45 with 43·9 as mean in S. commerson and 47–52 with 49·7 as mean in S. guttatus.