FISHERY BULLETIN: VOL. 73, NO. 3 



Figure 57.-Radiograph of the caudal complex with the bases of 

 the caudal fin rays covering the hypural plate. Orcynopsis 

 unicoLor, Dakar, 960 mm FL. 



followed by a series of anal finlets similar to the 

 dorsal finlets. Some scombrids have a free or par- 

 tially free spine preceding the anal fin, but in the 

 Sardini it is difficult to tell if the anterior elements 

 are spiny or soft rays so all are included as "anal 

 rays." Numbers of fin rays are useful taxonomic 

 characters in the Sardini. 



Using the number of dorsal spines (Table 10), 

 bonitos can be divided into three groups: few 

 spines (12-15) in Orcynopsis and Gymnosarda; 

 moderate numbers (16-19) in Cybiosarda, 

 Allothunnus, and three species of Sarda; and 

 many (20-23) in S. sarda. The difference between 

 these groups is correlated with the number of 

 vertebrae. Intraspecifically, eastern Atlantic 

 specimens of Sarda sarda have modally higher 

 counts (22) than western Atlantic specimens (21). 



The most distinctive bonito in counts of second 

 dorsal elements is Cybiosarda, with a high count of 

 17-19 rays (Table 11). Orcynopsis, Gymnosarda, 

 and Allothunnus have low counts (15 or fewer). 

 Sarda australis has, modally, one more second 

 dorsal ray than do S. orientalis and S. chiliensis. 



Species 



Table lO.-Number of spines in the first dorsal fin of species of Sardini. 

 11 12 13 14 15 16 17 18 19 20 21 22 23 



Cybiosarda elegans 



Orcynopsis unicolor: 

 E Mediterranean 

 Cent. Mediterranean 

 (Postel 1956a, Tunisia) 

 Atlantic 



Total 



Sarda australis 



Sarda chiliensis: 

 NE Pacific 

 (Kuo 1970) 

 SE Pacific 

 (Kuo 1970) 



Total 



Sarda orientalis: 

 Indian Ocean 

 NW Pacific 

 Cent. Pacific 

 E Pacific 



Total 



Sarda sarda: 

 North America 

 South America 

 NE Atlantic 



Mediterranean-Black Sea 

 (Demir 1964, Turkey) 

 Gulf of Guinea-S. Africa 



Total 



Gymnosarda unicolor: 

 Indian Ocean 

 W Pacific 



Total 



Allothunnus fallal 



12 9 1 



22 



1 28 7 

 10 



(3 22 161 3) 



4 2 



1 42 9 



7 12 



19 16 



(20 420 69 



5 19 7 



(8 77 5) 



5 38 23 



10 



11 4 



2 2 



4 11 1 



4 34 7 



16.5 



580 



