POTTHOFF: DEVELOPMENT AND STRUCTURE OF FINS IN CORYPHAENA 



Figure 23. — Caudal complex of a Coryphaena equiselis, 230 mm SL. For explanation of symbols, 

 see Figure 21. Stippled, articular cartilage; darkened, bone. 



Table U. — Distribution of principal caudal rays on the hypurals in 136 Coryphaena 

 hippurus (8.0-53 mm SL) (C. h.) and 75 C. equiselis (7.0-52 mm SL) (C. e.). 



epurals were autogenous. In part of the Scom- 

 bridae (Fierstine and Walters 1968; Monod 1968; 

 Patterson 1968; Collette and Chao 1975; Potthoff 

 1975) the anteriormost epural is secondarily fused 

 to the specialized neural arch of preural centrum 

 2. Based on the epurals, Coryphaena spp. is 

 advanced because epural numbers are reduced 

 from 3 to 2 and fused to 1 (Patterson 1968; 

 Fraser 1972). 



The haemal spines of preural centrum 2 and 3 

 were autogenous in Coryphaena spp. This state is 

 considered basic because advanced percoids have 

 these spines secondarily fused to the centra ( Fraser 

 1972). Fusion of these haemal spines occurs in 

 T. atlanticus (Potthoff 1975), and some apogonids 

 (Fraser 1972). 



The two prezygapophyses of the urostyle (Fig- 

 ure 24) oi Coryphaena spp. are true prezygapophy- 

 ses; whereas in T. atlanticus and other Thunnini 

 and Sardini (Collette and Chao 1975; Potthoff 

 1975) the prezygapophyses of the urostyle repre- 

 sent the pair of uroneurals which have fused to the 

 urostyle during development. 



Articular cartilage was present in Coryphaena 

 spp. on the caudal complex on all parts distally 

 inclusive of preural centrum 3. No articular car- 

 tilage was observed anterior to this centrum. 

 Articular cartilage was observed in scombrids by 

 Fierstine and Walters (1968), in T. atlanticus 

 by Potthoff (1975), and in A. rhomboidalis by 

 Houde and Potthoff (1975). The absence of artic- 

 ular cartilage in the caudal complex drawings of 



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