WATSON: DEVELOPMENT OF EGGS AND LARVAE OF WHITE CROAKER 



NS| PdB DP, DS| 



Figure 6.— Vertebral column and median fins of a 17.68 mm juvenile Genyonemus lineatus, showing typical relationships of dorsal 

 and anal pterygiophores to neural and haemal spines. NS, first neural spine on the first vertebra; PB, predorsal bones; DS, first 

 dorsal spine; DP, first dorsal pterygiophore; DR, first dorsal ray; HS, first haemal spine; AS, first anal spine; AR, first anal ray. 



Table 2.— Number of dorsal pterygiophores between adjacent 

 neural spines in Genyonemus lineatus. 



which is also associated with the first lower sec- 

 ondary caudal ray. Additional lower secondary 

 caudal rays apparently are becoming associated 

 with the haemal spine of the antepenultimate 

 vertebra in specimens larger than 10.5 mm. The 

 first (unossified) epural is associated with the 

 first upper secondary ray at 8 mm. There are five 

 supporting structures above the urostyle in spe- 

 cimens larger than 10.5 mm; the anterior three 

 appear to be associating with the neural spine of 

 the penultimate vertebra, and support five sec- 

 ondary caudal rays. Additional dorsal secondary 

 rays in larger larvae are supported by the neural 

 spine of the antepenultimate vertebra. 



Proportions 



Larval development of G. lineatus is a gradual 

 process without rapid changes in body propor- 



tions: all body parts measured are linearly re- 

 lated to standard length through the larval peri- 

 od (Table 3). Since it is of little value to describe 

 such growth only a summary of measurements is 

 given (Table 4). 



Table 3.— Summary of regressions of measure- 

 ments of body parts (y) on standard length (x) of 

 Genyonemus lineatus larvae. 



COMPARISON WITH SIMILAR 

 SPECIES 



Genyonemus lineatus eggs closely resemble 

 those of many other fish which spawn in the near- 

 shore coastal waters off southern California. 

 Consequently, separation to the species level is 

 difficult and of doubtful practicality in the rou- 

 tine identification of ichthyoplankton samples. 



Among the fish larvae commonly taken in in- 

 shore plankton samples along the southern Cali- 

 fornia coast, G. lineatus most closely resembles 



413 



