FISHERY BULLETIN: VOL. 78, NO. 2 



2.9nnmSL 



4.0 mm SL 



4.1 mm SL 



Figure 2. — Isopsetta isolepis larvae: 2.9 mm SL (reared, newly hatched, 144 h after fertilization); 4.0 

 mm SL (reared, 4 d after hatching); 4.1 mm SL (plankton specimen). 



it, first in the region of the anterior two pigment 

 bands in larvae about 6 or 7 mm long. Additional 

 internal pigment spots then develop along the 

 notochrod between the three pigment bands and 

 anterior to them. This line of internal pigment 

 spots is usually not continuous. It remains visible 

 until the end of the transformation period. Along 

 the ventral midline, pigment appears as a charac- 

 teristic double row (viewed ventrally) of small 

 melanophores in larvae >4 mm. This double row 

 remains obvious until the onset of anal fin forma- 

 tion, about 14 mm, after which these mela- 

 nophores appear to line the base of the anal fin, 

 sometimes with one melanophore/fin ray. These 

 melanophores become indistinct during trans- 



406 



formation. On the ventrolateral body surface, 

 melanophores are added just above the ventral 

 midline row about the time the anal fin begins to 

 form, around 10 mm. These melanophores even- 

 tually, by 12 mm, appear in the myosepta in a line 

 midway between the lateral midline and the ven- 

 tral margin of the body myomeres. Until the addi- 

 tion of pigment during transformation this line of 

 melanophores is visible on the eyed side only, but 

 is often visible on the blind side of newly trans- 

 formed benthic juveniles. Along the margin of the 

 ventral finfold a line of evenly spaced small 

 melanophores is visible on newly preserved larvae 

 >4 mm. This is often faded after a long period of 

 preservation or is missing in plankton collected 



