two of our three specimens of T. maccoyii the branch- 

 ing occurred near the end of the tail of the kidney. 



In T. maccoyii, the dorsal aorta was reported to 

 be usually conspicuously constricted behind the ori- 

 gin of the cutaneous arteries. We observed this 

 condition in both T. i. thynnus and T. t. orientalis, 

 but size did not decrease in our specimens of T. 

 maccoyii. 



The presence of a connecting branch between the 

 two main branches of the coeliacomesenteric artery 

 was said to distinguish T. t. orientalis and T. maccoyii 

 from T. t. thynnxis; however, Godsil and Holmberg 

 (1950) did not find the branch in one Australian 

 specimen and they were uncertain as to its presence 

 in another. Furthermore, we observed this connec- 

 tion in several western Atlantic specimens. 



The cutaneous artery in T. maccoyii was said to 

 pass laterally most often between ribs 2 and 3 (rather 

 than 3 and 4) and to divide usually between inter- 

 muscular bones 5 and 6 (rather than 4 and 5). 

 Godsil and Byers (1944) recorded this condition as 

 rare in T. t. orientalis, and Godsil and Holmberg 

 (1950) noted the same for T. t. thynnus. In all our 

 material, including T. maccoyii, the artery passed 

 between ribs 3 and 4, and divided between intermus- 

 cular bones 4 and 5 (between 5 and 6 in one specimen 

 of T. t. thynnus). 



The place of attachment of the internal wing of the 

 pelvic girdle was said to be different in each of the 

 three forms (Godsil and Holmberg, 1950). AVe 

 found the condition in all three similar to their 

 descriptions of T. maccoyii. 



THUNNUS MACCOYII (Castelnau, 1872) 

 SOUTHERN BLUEFIN TUNA 



Thynnus maccoyii Castolnan, 1872: 104-105 (original 

 description; Melljourne market). 



Thunnus phillipsi Jordan and Evermann, 1926: 13 

 (original description; New Zealand), "pi. 2, fig. 4. 



Thunnus maccoyii, Jordan and Evermann, 1926: 13 

 (description). Serventy, 1941: 27-33 (descrip- 

 tion; Australia), fig. 5, pi. 2. Godsil and Holm- 

 berg, 1950 (comparison of Australian with New 

 England and California specimens; anatomy). 

 Mimura and Warashina, 1902. Iwai and Naka- 

 mura, 1964: 6, figs. 3E, F (olfactory rosettes). 

 Iwai et al., 1965: 9 (synonymy), 33-34 (descrip- 

 tion), fig. 18. Nakamura, 1965: 18, figs. 3C, 5C, 

 7 (osteolog.y). Nakamura and Kikawa, 1966 

 (infracentral grooves). 



Thunnus obesris, Fraser-Brunner, 1950: 144 (T. 

 maccoyii in synonym^')- 



Thunnus thynnus maccoyii, Serventy, 1956a (coimts, 

 distribution around Australia). Monro, 1958: 

 111 (Australia). Robins, 1963 (biologj'; Aus- 

 tralia) . 



Th%innus thynnus subspecies, Serventy, 1956a: 13 

 (probably a separate subspecies in S. Africa). 



Thunnus thynnus orientalis, Jones and Silas, 1960: 

 381-382 (Indian Ocean), fig. 8. Collette and 

 Gibbs, 1963: 28. Jones and Silas, 1963: 1788- 

 1790 (Indian Ocean). Talbot and Penrith, 1963: 

 630-636 (description, biology; S. Africa). Jones 

 and Silas, 1964: 30-34 (Indian Ocean). 



Types of Nominal Species 



Thynnus maccoyii Castelnau, 1872. No type 

 specimens. Bauchot and Blanc (1961: 377) re- 

 ported that a type specimen was catalogued in the 

 collections of the Museum National d'Histoire 

 Naturelle, Paris, in 1877, as number 515, but that 

 the specimen cannot be located. Original descrip- 

 tion based on several specimens, fresh and dried, 

 from the Melbourne, Australia, market, the largest 

 23 inches (585 mm.) long. This description is inade- 

 quate, but the short pectoral (two-thirds of head) 

 suggests one of the bluefin tunas or T. tonggol, and 

 the locality rules out all except T. maccoyii as now 

 recognized. 



Thunnus phillipsi Jordan and Evermann, 1926. 

 Type originally designated as "A photograph. No. 

 596, Mus. Calif. Acad. Sci. ... of a specimen taken 

 in the Bay of Islands, New Zealand." This photo- 

 graph is of a pug-headed mounted specimen in the 

 Dominion Museum, Wellington. The cast is 1,575 

 mm. FL. The pectoral fin is short (295 mm.), which 

 makes T. maccoyii the only reasonable assignment 

 for this nominal species, T. tonggol not being knowTi 

 to occur in New Zealand. According to J. Moreland 

 (pers. comm.), the pug-headedness appears to be the 

 result of the fish being stood on its head forcing the 

 processes of the premaxillaries up over the frontals 

 where they remained when the cast was made. 



Characters 



Pectoral fin short, not more than 80 percent of 

 head length, 20-23 percent of fork length in speci- 

 mens 650-1,450 mm. (overlapping T. tonggol; 

 slightly longer than T. thynnus). Caudal keels yel- 

 low in most specimens: this color possibly lost in 

 larger adults. 



ANATOMY AND SYSTEMATICS OF TUNAS 



115 



