Wild. A., and T. J. Foreman. 



1980. The relationship between otolith increments and 

 time for yellowfin and skipjack tuna marked with tetra- 

 cycline. Inter-Amer. 'Prop. Tuna Comm., Bull., 17:509- 

 560. 



Terry Foreman 



Inter-American Tropical Tuna Commission 

 Scripps Institution of Oceanography 

 La Jolla. CA 92093 



SECOND RECORD OF THE KAWAKAWA, 



EUTHYNMS AFFIMS. 



FROM THE EASTERN PACIFIC OCEAN 



Although the kawakawa, Euthynnus affinis 

 (Cantor 1849), is widely distributed throughout 

 the warm waters of the Indo-West Pacific 

 (Yoshida 1979), it is replaced by the black skip- 

 jack, E. lineatus Kishinouye, in the eastern 

 Pacific. There is only one previous record of E. 

 affinis in the eastern Pacific. That specimen, 361 

 mm fork length (FL), was reported from Los An- 

 geles Harbor, CA, in 1952 (Fitch 1953). The sec- 

 ond documented occurrence of £■. affinis from the 

 waters of the eastern Pacific is recorded in this 

 note. 



The specimen, E. affinis , 920 mm FL and 13.15 

 kg, was caught by Ronald Nakamura using hook 

 and line from the long-range San Diego-based 

 sport-fishing boat. Royal Polaris , on 17 December 

 1986, off Clarion Island (lat. 18°22'N, long. 

 114°44'W) in the Revillagigedo group. The speci- 

 men has been deposited in the Scripps Institution 

 of Oceanography fish collection (SIO 87-70). 



The morphometric and meristic characters for 

 the specimen are given in Table. 1. The measure- 

 ments were taken according to the methods of 

 Godsil and Byers (1944) and Gibbs and Collette 

 (1967). The external characters of this specimen 

 agree with Godsil's (1954a) description of the spe- 

 cies. The wavy oblique markings on each side of 

 the dorsal surface, no dip in the lateral line below 

 the second dorsal fin, and the several black to 

 gray spots scattered over a relatively wide area 

 between the pectoral and pelvic fins are charac- 

 teristic of most specimens of this species. Further- 

 more, the morphometries for this specimen are 

 within the ranges for those body proportions re- 

 ported by Godsil (1954b) and are closer to the 



morphometries for E. affinis from Hawaii, rather 

 than from Japan. 



The internal characters also appear to agree 

 with Godsil's (1954a) description of the species. 

 High-quality radiographs produced by computer- 

 assisted tomography (C.A.T.) scanning equip- 

 ment were utilized for examing skeletal charac- 

 ters. The vertebral count is 20 + 19 = 39, and the 

 radiographs showed no bony protuberances on 

 any of the caudal vertebrae. However, no vomer- 

 ine teeth were present. Although there was no 

 indication of their previous presence, their ab- 

 sence could be explained by wear in this pre- 

 sumably old specimen. Nevertheless, the primary 

 characters distinctive of £". affinis, 39 vertebrae, 

 the total gill raker count of 31, and the absence of 

 bony protuberances on the caudal vertebrae, 

 leave no doubt on the identity of this specimen. 



The occurrence of E. affinis, as well as the first 

 documented occurrence of this specimen in the 

 eastern Pacific, should be considered extremely 

 rare events. No specimens of E. affinis were 

 noted, during 1980-82 while personally examin- 

 ing a few thousand specimens of E. lineatus 

 landed by commercial tuna vessels operating in 

 the eastern Pacific. One of the remarkable fea- 



Table 1. — Summary of morphometric and meristic 

 data. The measurements are in millimeters. 



FISHERY BULLETIN; VOL. 85. NO. 3, 1987. 



647 



