FISHERY BULLETIN: VOL. 72. NO. 2 



S 15 



Y> -0 1089*0 1366 X 



'.09928 



n.l9l 



.^■^ 



STANOASD LENGTH (MM) 



Snout-to-Anus Length 



The snout-to-anus length increased 0.5347 mm 

 for each millimeter increment in standard length 

 throughout larval development (Figure 7). As 

 might be expected from the body depth differences 

 between omaka and jack mackerel, the ratio 

 between snout-to-anus length and standard 

 length of omaka is slightly smaller than that 

 for the jack mackerel (0.581), the latter being 

 a more elongate larva. Again, however, the 

 difference is probably too small to be useful 

 in separating the species. 



Figure 6. — Relationship between standard length and eye 

 diameter ofCarartx mate larvae. 



standard length was described by a straight line 

 of the equation: ED = -0.1089 + 0.1266 (SL in 

 mm) (Figure 6). Omaka larvae have almost the 

 same (proportional) eye size as T. symmetricus 

 (0.127), reported by Ahlstrom and Ball (1954). 

 Therefore, this ratio is not useful. as a dis- 

 tinguishing characteristic. 



The omaka eye was somewhat ovoid with the 

 blunt end anterior. The posterior, more acute, 

 end of the eye became more angled up to day 4, 

 then the trend was reversed so the juvenile 

 round eye shape was reached by day 20 (SL = 

 8.27). The "squarish distortion" reported for T. 

 symmetricus (Ahlstrom and Ball, 1954) did not 

 occur in omaka. 



Body Depth at Pectoral Insertion 



The relationship between the body depth and 

 standard length remained constant throughout 

 larval development (Figure 8). No inflection was 

 evident in the omaka, as was reported for T. 

 symmetricus by Ahlstrom and Ball, 1954 (larvae 

 smaller than 4.2 mm). The slopes of the regres- 

 sion lines (0.425 for omaka and 0.278 for jack 

 mackerel larvae) are different enough to be used 

 to distinguish these species over 4 mm; omaka 

 larvae are considerably deeper-bodied. The other 

 common carangid in Kaneohe Bay, G. speciosus, 

 has a still deeper-bodied larva (our unpublished 

 data); so this ratio appears the most useful of 

 the four discussed to distinguish at least these 

 three species. 



• 1223.0 5347 X 

  09972 



_1 1 l_ 



STANDARD LfNGTH (MM) 



6 3 



Y. -0 S583 *OA24bx 



f .0 9953 



n.l9) 



S 10 



STANDARD LENGTH (MM) 



Figure 7. — Relationship between standard length and snout- 

 to-anus length ofCaranx mate larvae. 



Figure 8. — Relationship between standard length and body 

 depth oCCaranx mate larvae. 



512 



