FISHERY BULLETIN: VOL. 78, NO. 2 



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Figure 27. — Lateral external view of left side of pectoral girdle 

 from a 8.1 mm SL Coryphaena hippurus (left) and a 7.9 mm SL 

 C. equiselis (right). Symbols: ScF, scapular foramen. For 

 explanation of other symbols, see Figures 25, 26. Stippled, 

 cartilage; darkened, bone. 



tilage consisted of a long dorsal process, a long 

 posterior process, and a short anterior process. 

 Houde and Potthoff (1976) found that the anterior 

 process of the coraco-scapular cartilage formed 

 after the formation of the dorsal and posterior 

 processes in labor atory -reared A rcAosar^ws rhom- 

 boidalis larvae. I believe that both species of 

 Coryphaena have the same kind of cartilage 

 development as A. rhomboidalis. At 5.5 mm NL, 

 C. hippurus first developed the supracleithrum, 

 and after 6.3 mm NL, it was always present. The 

 supracleithrum at first was a small rod-shaped 

 bone, which only gradually acquired its flattened 

 paddlelike shape. The cleithrum and the coraco- 

 scapular cartilage did not show any development 



between 5 and 7.3 mm NL. The posttemporal first 

 developed as a small, rod-shaped bone at 6.3 mm 

 NL. In larvae of 7.4 mm SL the scapular foramen 

 was first seen in the dorsal process of the coraco- 

 scapular cartilage, and at 7.6 mm SL the posterior 

 process of the cleithrum first appeared (Figure 

 27). Between 7.6 and 8.4 mm SL many develop- 

 mental changes occurred. In an 8 mm SL specimen 

 the first dorsalmost radial was seen in cartilage; 

 the radial was absent in an 8.1 mm SL specimen 

 (Figure 27), but present again at 8.3 mm SL. The 

 bony rod-shaped postcleithrum 2 was first seen at 

 8.3 mm SL. Ossification of the coraco-scapular 

 cartilage started at 8.1 mm SL in the region of the 

 future coracoid at the juncture of the dorsal and 

 anterior processes. The scapula started to ossify 

 first around the scapular foramen at 9.5 mm SL. 

 Also at 9.5 mm SL the postcleithrum 1 was first 

 seen as a tiny speck of bone, but not until 11.9 mm 

 SL was this structure easy to see. All four radials 

 were present at 11.9 mm SL; the dorsalmost was 

 starting to ossify and the following three were 

 in cartilage. All radials in C. hippurus were 

 ossifying by 12.3 mm SL (Figure 29). The supra- 

 temporal was first seen at 18 mm SL as a single 

 lateral line pore situated anterior to the post- 

 temporal (Figure 25). Its development was diffi- 

 cult to trace because the adult bone was very thin, 

 but distinctive because it was traversed by a 

 lateral line canal. With increasing size more pores 

 appeared, some at a distance dorsad for the two 

 intertemporal and others adjacent to the first 

 pore for the supratemporal. These pores even- 

 tually joined to form two tubular canal bones, 

 the intertemporals and the thin supratemporal. 

 Further development of the bones in the pectoral 

 girdle and suspensorium of C. hippurus past 

 12.3 mm SL (when all component bones are ossi- 



TABLE 12. — Development of structures, bones and fin rays of the pelvic and pectoral girdles for the two species of Coryphaena, shown 

 for lengths (in millimeters NL or SL) at which structures, bones or fin rays first appear in cartilage or ossify. Lengths given signify a 

 first observance and do not necessarily apply to all specimens of that length or longer. 



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