APRIETO: EARLY DEVELOPMENT OF FIVE CARANGID FISHES 



Table 4— Measurements (mm) of larvae and juveniles of Seriola zonata. 

 (Specimens between dashed lines are undergoing notochord flexion.) 



increases with growth and at 15 mm four loops are 

 present. Snout-to-anus distance increases in rela- 

 tion to standard length. It is 58.39c at 3.6 mm and 

 gradually increases to 70^^ at transformation. 

 Hypaxial musculature develops at 6 mm and com- 

 pletely surrounds the abdominal cavity except at 

 the gut opening at 10 mm. 



There are 24 myomeres — 10 preanal plus 14 

 postanal — throughout the larval and juvenile 

 stages. 



Pigmentation 



Larval pigmentation consists of conspicuous 

 melanophores along the bases of the dorsal and 

 anal fins, on the lateral midline, and in the 

 peritoneum lining the middorsal wall of the ab- 

 dominal cavity. In a freshly preserved 9-mm larva 

 there are dense concentrations of xanthophores on 



the head, preopercle, and on the back and upper 

 sides of the body while iridiophores are profuse on 

 the sides of the body below the lateral midline. In 

 older larvae, the melanophores are apparently ac- 

 tively expanding and contracting as most larvae 

 have either contracted melanophores and are pale 

 looking, or are dark when the melanophores are 

 expanded. Other larvae have alternating patches 

 of expanded and contracted melanophores form- 

 ing false bands (Figure 3F-H). In early juveniles 

 (17 mm), the body definitely becomes banded. A 

 bold color pattern develops including a distinct 

 nuchal bar and 6 solid bands which extend to the 

 dorsal and anal fins (Figure 31). In a young 

 juvenile 23 mm long, the lobes of the unpigmented 

 caudal fin have a brown spot developing at the 

 tips. Alcohol-preserved metamorphic larvae and 

 early juveniles have chocolate-brown bands over a 

 silvery background. With the exception of 



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