FISHERY BULLETIN: VOL. 73, NO. 3 



Cybiosarda has, modally, nine dorsal finlets; Gym- 

 nosarda, Allothunnus, and S. australis have 

 seven; and the other four species have eight. Thus, 

 in total number of second dorsal elements, 

 Cybiosarda is high (25-27), Gymnosarda and 

 Allothunnus are low (19-21), and the other species 

 are intermediate. 



Anal rays (Table 12) follovi^ a similar trend to 

 that of dorsal rays. Cybiosarda has many anal rays 

 (15-17) and total anal elements (21-24). Gym- 

 nosarda has few anal rays (12-13) and total anal 

 elements (18-19). Modally, Cybiosarda, Orcynop- 

 sis, Allothunnus, Sarda chiliensis, and S. sarda 

 have seven anal finlets; Gymnosarda, Sarda aus- 

 tralis, and S. orientalis have six finlets. 



PECTORAL GIRDLE 



a flat posterior body (Figure 58). The median 

 process is thin and flat and articulates v^^ith the 

 epiotic. The lateral process is rounded and rodlike 

 and articulates with the intercalar anteroven- 

 trally. Cybiosarda, Orcynopsis, Sarda, and 

 Allothunnus each have a well-developed shelf 

 connecting the median and lateral processes while 

 Gymnosarda (Figure 58e) has the shelf greatly 

 reduced. The shelf extends posteriorly and forms a 

 posteriorly directed spine beneath the body in all 

 bonitos. Cybiosarda, Orcynopsis, and Gymnosarda 

 have a shorter body than do Sarda and Allothun- 

 nus. There is a notch at the middle of the posterior 

 edge of the body of the bone. The dorsal profile of 

 the posttemporal is more or less flat in all the 

 bonitos except in Gymnosarda, which has the 

 margin convex posteriorly. 



The pectoral girdle consists of the girdle itself 

 (cleithrum, scapula, and coracoid), the radials to 

 which the pectoral fin rays attach and a chain of 

 bones that connect the girdle onto the rear of the 

 skull (posttemporal, supratemporal, supracleith- 

 rum, and two postcleithra). 



Posttemporal 



The posttemporal bones of the bonitos are 

 generally similar with two anterior processes and 



Supratemporal 



The supratemporal bones of the bonitos are thin 

 with two anterior processes and an elongated 

 posterior body (Figure 59). The dorsal process lies 

 free beneath the skin and the ventral process is 

 firmly attached with connective tissue. The 

 posterior body of the supratemporal overlaps ex- 

 ternally the lateral process and part of the 

 posterior body of the posttemporal. Lateral line 

 canals are present on the internal surfaces of the 



MEDIAN PROCESS 



LATERAL PROCESS 



Figure 58.-External view of left posttemporals of six species of Sardini. a. Cybiosarda elegans, New South Wales, 355 

 mm FL. b. Orcynopsis unicolor, Tunisia, 645 mm FL. c. Sarda sarda, Tunisia, 504 mm FL. d. Sarda australis, New 

 South Wales, 363 mm FL. e. Gymnosarda unicolor, Truk Islands, 784 mm FL. f . Allothunnus fallai, California, 680 mm 

 FL. 



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