Fig. 72 — Capture localities in the eastern Pacific Ocean for Gonichthys tenuicutus (small 

 solid circles), G. venetus (large open circles), G. venetus s. sp. (open squares), G. cocco 

 (open triangles), and G. barnesi (solid triangles). 



Bolin (1959) stated that a form with an incomplete lateral line ranged westward from the 

 coast of South America in a narrow band centered on 25° S; he further stated that it was 

 uncertain whether these fishes represented an isolated population of Gonichthys cocco (Cocco, 

 1829) or an undescribed species. As suggested by Becker (1964a), it is probable that this form 

 is referrable to G. venetus. 



However, Becker stated that G. venetus is closely related to G. cocco and it may eventually 

 be reduced to a subspecies. The principal character separating the two is that in G. cocco the 

 last perforated scale of the lateral line lies under or in advance of the tip of the adipose fin 

 (Bolin, 1959, key). Becker (1964a) gave a somewhat more anterior position for this scale, 

 "beside a vertical from the origin of the adipose base," and stated that in G. venetus only the 

 last 3 to 6 lateral line scales were unperforated. 



Most of Becker's study material (124 specimens) of G. venetus was from the west-central 

 Pacific Ocean, northerly of New Zealand, and formed the basis for diagnosis of the species; all 

 these specimens apparently have the last 3 to 6 lateral line scales unperforated. Becker 

 discussed as a possible subspecies seven specimens from near the equator between about 140° 

 and 155° W (Fig. 72, solid squares) that differed from the rest of the material principally in 

 having all the lateral line scales perforated. Becker also stated that these specimens had a 



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