Fig. 49 — Myctophum phengodes, male, 54.5 mm. 



Fig. 50 — Supracaudal gland of the male M. phengodes shown in fig. 49. 



Six to 8 luminous scales in the supracaudal gland are evident at about 30 mm (Fig. 50); 3 

 or 4 luminous scales in the infracaudal gland. The limited material at my disposal does not 

 permit an estimate of size at early development. 



Size: To about 60 mm. 



Least depth of capture: At surface at night. Craddock and Mead ( 1970) reported the 

 capture of 614 specimens from the southeastern Pacific Ocean, off Chile, between about 30° 

 and 34° S, 77° and 92° W; of this number, 320 were taken with surface nets at night, the rest by 

 subsurface trawl. 



Distribution: Apparently circumglobal only in southern oceans from about 25° to 50° S. 

 Fowler (1901, p. 260) identified as Myctophum phengodes a specimen from 60° N, between 

 Greenland and North America (the Labrador Sea). I have examined this specimen (ANSP 

 7987, 79.5 mm SL) and found it to be Myctophum punctatum Rafinesque, 1810, a very common 

 species of the North Atlantic Ocean. 

 Discussion 



Only 11 specimens were available to me for study: 4 from the southeastern Pacific Ocean, 

 6 from the Indian Ocean, and 1 from the southeastern Atlantic Ocean. Among these few 

 specimens an interesting difference was observed in position of the Pol photophore relative to 

 the base of the adipose fin. In the four specimens from the southeastern Pacific, Pol was under 

 only the first or second lateral line pore before end of adipose base; in the six specimens from 

 the Indian Ocean, Pol was under the third or fourth pore; and in the single specimen from the 

 southeastern Atlantic, Pol was under the third pore. Both sides of each specimen were 

 examined. Counts on these few specimens indicated no significant differences among the three 

 areas. 



57 



