Fig. 129— Diaphus anderseni . From Taning (1932, p. 134, fig. 6). 



Size: To about 35 mm. 



Least depth of capture: To about 24 m at night. 



Distribution: Although the type locality is southwest of Fiji, the species is very common in 

 the northeastern Pacific Ocean (Fig. 124). 



Notolychnus Fraser-Brunner, 1949 



Frontal bones expanded into a small, but conspicuous, median, transparent dome into 

 which the pineal organ extends. Adipose fin far behind end of anal base. Two Pre arranged 

 vertically. Five PO, the third notably, the fourth markedly, elevated. Four VO, the first 

 elevated. VLO, SAO;,, and upper Pol very high, near dorsal profile. Dn present; no Vn. A single 

 deeply set translucent supracaudal luminous gland present in both sexes; no infracaudal 

 glands. Males have a much larger eye and supracaudal gland than do females. Lateral line 

 obsolete. 



Photophores are easily lost on this diminutive species, but the supracaudal gland, or a 

 portion of it, usually remains. If this gland is also lost, the far-back portion of the adipose fin is 

 diagnostic, as are the low number of pelvic rays (6). 



A single species is recognized. 



Notolychnus valdiviae 



(Brauer, 1904) 



Fig. 130 — Notolychnus valdiviae (Brauer, 1904). (A.) Adult male (note large eyei, (B.) 

 Dorsal view of male caadal peduncle, (C.l Head of adult female, (D.) Caudal peduncle of 

 adult female, lE). Dorsal view of female caudal peduncle. From Bolin (1946, p. 147, fig. 

 9i. 



144 



