THE SHORE FISHES OF PERU 369 



small, those on vomer and palatines in villiform patches; gill rakers 

 long, moderately slender; scales covering entire body, enlarged, and 

 forming a corselet in region of pectorals; interval between dorsal 

 fins slight; first dorsal with 12 to 15 rather slender spines, the fin 

 high anteriorly; second dorsal and anal each followed by 8 or 9 finlets; 

 ventral fins rather small, less than half length of head; pectoral short 

 or long, with about 32 to 35 rays. 



A single species was taken on the coast of Peru. However, the 

 common bluefin tuna, T. thynnus (Linnaeus), which is widely distrib- 

 uted and has been recorded from the GaMpagos Islands, may be ex- 

 pected in Peru. Another tuna, often listed as Germo alalunga 

 (Gmelin), if one considers the Atlantic and Pacific Ocean inhabitants 

 identical, concerning which there still is considerable doubt, or as 

 G. germo (Lacep^de) if one considers the ones from the Pacific Ocean 

 different from those from the Atlantic, almost certainly will be taken 

 sooner or later in Peru, as it occurs both north and south of this 

 country. A specimen from Chile (U.S.N.M. No. 22975) is before me. 

 This is the common "albacore" of California, highly prized as a canned 

 product. I provisionally use the name germo. The two species 

 named, for which no descriptions are given herein, may be identified 

 from the key that follows. 



KEY TO THE SPECIES 



a. Pectoral fin notably shorter than head, failing to reach origin of second 

 dorsal, 4.8 to 5.6 in length; 26 or 27 gill rakers on lower limb of first arch; 

 small specimens, at least, with pale spots and bars on lower part of side. 



(Data based on Atlantic specimens.) thynnus 



aa. Pectoral fin about equal to or a little longer than head, reaching to or more 

 usually beyond origin of dorsal, but not to origin of anal, 3.3 to 3.6 in 

 length; 20 to 22 gill rakers on lower limb of first arch; small specimens, 

 at least, with pale spots and bars on lower part of side. (Data based on 



Peruvian specimens.) macropterus (p. 369) 



aaa. Pectoral fin very long, reaching to or beyond origin of anal, 2.3 to 3.0 in 

 length; 21 or 22 gill rakers on lower limb of first arch; small specimens, 

 at least, with pale longitudinal streaks along lower part of side. (Data 

 based on a specimen from California and on one from Chile.) germo 



THUNNUS MACROPTERUS (Schlegel) 



Atxjn; Tunc; Albacora 



Thynnus macropterus Schlegel, 1850, p. 98, pi. 51, Japan (original description). 



Neothunnus macropterus Kishinquye, 1923, p. 446, figs. 13, 19, 23, 45, and 51 

 (synonymy; description; distribution; size attained; habits; food; properties 

 of the flesh; spawning; relationship).— Herre, 1936, p. 106, Galdpagos 

 Islands (synonymy; discussion; range). — Walford, 1937, p. 3, pi. 33 in color 

 (compared with bluefin tuna; size; distribution; food; spawning; migrations; 

 game qualities). 



tGermo argentivittatus Nichols and Murphy, 1922, p. 507, pi. 25, Peru (notes; 

 identification based on a photograph). 



Neothunnus albacora Nichols and LaMonte (in part?), 1941, p. 30 (synonymy; 

 discussion of synonymy, of development of dorsal and anal lobes, and of 

 yellowfin tunas from the Atlantic and Pacific.) 



