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Fishery Bulletin 88(3|, 1990 



trend for the Gulf of Mexico. Of the larvae shown in 

 Table 2, 78.7% are definitely atlanticus with 10.9% 

 albacares or obesus. The two alalunga were a surprise, 

 as the adults of that species have not been taken in the 

 Gulf of Mexico (Collette and Nauen 1983:81); but given 

 the variability found in these larval characters, these 

 data should not be used as unequivocal criteria for 

 recording this species in the Gulf. We have speculated 

 on the identity of the specimens listed in Table 3; as 

 one can see, this speculation raises possibilities but not 

 certainties. 



Thunntis atlatitirus is very common in the Gulf of 

 Mexico and spawning is widespread as evidenced by 

 larval data ( Richards et al. 1984). Thunnus albacares 

 supports a developing fishery, but spawning may not 

 be as widespread based on our 1982 data. In future 

 studies focusing on albacares, researchers will have to 

 use cleared and stained specimens to confirm larval 

 abundance reliably, since about 50% of those larvae 

 lacking ventral tail pigment may be atlanticus morphs 

 or possibly even alalunga (Table 2). Recently, Graves 

 et al. (1989) have shown that small juveniles 10-21 mm 



