FISHERY BULLETIN: VOL. 77. NO 1 



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Figure 21, — Early juvenile o{ Hypsopsetta guttulata. 1.3.2 mm. 



coenosus and P. uerticalts due to similarities in 

 size and pigmentation of the larvae, and the pres- 

 ence of pigment on the finfold dorsally and ven- 

 trally, posterior to the anus. Characters of H. 

 stomata larvae which distinguish them from 

 preflexionP. coenosus larvae include the presence 

 of a pigment bar through the eye, heavy pigment 

 on both sides of the pectoral fin base and a sprinkl- 

 ing of pigment on the pectoral blade, a more slen- 

 der, elongate body, and a significantly smaller 

 patch of dorsal finfold pigment. The same charac- 

 ters help to distinguish H. storjiata from P. ver- 

 ticalis. except for the finfold pigmentation. 

 Pleuronichthys verticalis has small, triangular- 

 shaped pigment patches whereas H. stomata has a 

 small rounded pigment cluster on the dorsal 

 finfold and a broad patch on the ventral finfold. 

 Larvae of P. verticalis are also smaller than H. 

 stomata at similar developmental stages. 



Larvae in the flexion stage and larger are read- 

 ily separable from Pleuronichthys by the preoper- 

 cular spines and development of several elongated 

 dorsal rays in the anteriormost part of the dorsal 

 fin. These do not develop on larval Pleuronichthys 

 or Hypsopsetta. 



L36 



Pigmentation. — Yolk-sac larvae (ca. 3.7 mmi are 

 heavily pigmented on the trunk and tail except for 

 the posteriormost part of the tail which is pig- 

 mented with several small spots dorsally and ven- 

 trally (Figure 23A). The upper head and abdomi- 

 nal region have scattered pigment, with a more 

 concentrated bar of pigment on each side of the 

 eye. Both sides of the pectoral fin base are con- 

 spicuously pigmented. Finfold pigment consists of 

 a small, rounded patch at the edge of the dorsal 

 finfold, and a broad patch on the ventral finfold, 

 both situated posterior to the anus near the mid- 

 point between the anus and tip of the tail (Figure 

 23Ai. 



Preflexion larvae, 4. 1-7.0 mm NL, undergo little 

 change in pigmentation except to augment pig- 

 ment in areas of the pectoral fin, abdominal re- 

 gion, and top of the head (Figure 23Bi. 



On larvae forming the dorsal and anal fins, the 

 dorsal finfold pigment spreads to include the area 

 between the fin rudiments and body margin, and 

 the ventral finfold pigment spreads both an- 

 teriorly and posteriorly (Figure 23C). Pigment on 

 the pectoral fin base intensifies and also extends 

 out onto the fin blade. 



