Distribution: In the eastern Pacific a single specimen (46.3 mm), a male with moderately 

 well-developed testes, is known from about 25° S, 155° W. The species is also known from the 

 North Atlantic Ocean and is common off South Africa. I have examined specimens from the 

 Indian Ocean (25° 24' S, 35° 41' E) and from the Indo-Pacific area (ca 13° N, 111° E). Whitley 

 (1968) did not list the species in his checklist of New Zealand fishes. 



The Diaphus fulgens-rafinesquii Species Complex 

 in the Pacific Ocean 



During this study I encountered eight apparently distinct diaphid species that correspond 

 reasonably well to Z)/ap/!t/s/'(//j^e/!s Brauer (1904). One of these forms is almost certainly 

 Diaphus mollis Taning (1928), and three appear to be allied to D. rafinesquii (Cocco, 1838). I 

 believe the remaining four to be most closely related to D. fulgens, but as I am unable to assign 

 any of the four to Brauer's species, I diagnose them only as Forms A, B, C, and D. Similarly, I 

 diagnose the three D. rafinesquii -like forms as Forms R-1, R-2, and R-3. The affinities of the 

 seven presently unassignable forms to described species will be discussed after their diagnoses. 

 The following key will aid in the identification of the Forms. 



Key to the identification of Forms A, B, C, and D 



of the Diaphus fulgens complex and Forms R-1, R-2, and 



R-3 of the D. rafinesquii complex in the Pacific Ocean. 



la. Total gill rakers 21 or less (rarely 22). The D. fulgens complex 2 



lb. Total gill rakers 22 or more. The D. rafinesquii complex 5 



2a. Upper gill rakers 3 to 4 3 



2b. Upper gill rakers 5 to 6 4 



3a. Gill rakers 4 -h 1 + 10 (9-11), total 15 (14-16). No luminous scale at PLO. Enlarged Vn of 



males in two parts, the anterior the largest Form A 



3b. Gill rakers 3-4-1-1 + 9 (8-10), total 14 (13-15). A large luminous scale present at PLO, the 



tissue in horizontal lines. Enlarged Vn of males undivided Form B 



4a. Gill rakers 6 (5) + 1 + 12-13 (14), total 19-20 (18-22). Luminous scale at PLO large, the 

 tissue in straight lines slanting more or less posteroventrally. Enlarged Vn of males 

 undivided. Body photophores small. V0:;.3 interspace 72% (60-86%) of space between VLO 



andVO, Form C 



4b. Gill rakers 5 + 1 + 10-11 (12), total 16-17 (15-18). Luminous scale at PLO large, the tissue 

 in steep, posteroventrally slanting, often nearly vertical lines. VO2-3 interspace 48% (39- 



55%) of space between VLO and VOj FormD 



5a. Length of orbit 51% (49-56%) of length of upper jaw. Length of anal base 84% (79-93%) of 

 length of dorsal base. VO,..;, interspace 52% (40-60% ) of space between 



VLO and VO. Form R-2 



5b. Length of orbit 46% to 48%- (44-52% ) of length of upper jaw 6 



6a. Length of orbit 46% (44-48%) of length of upper jaw. Length of anal base 77% (74-80%) of 

 length of dorsal base. VO2-3 interspace 61% (56-67% ) of space between 



VLOandVOo Form R-1 



6b. Length of orbit 48% (45-52% ) of length of upper jaw. Length of anal base 83% (75-91%) of 

 length of upper jaw. VO,.;, interspace 57% (53-62% ) of space between VLO and VOo (in 

 young fish, 37 to 57 mm) FormR-3 



Meristic data for Diaphus mollis. Forms A, B, C and D of the D. fulgens species complex 

 and Forms R-1, R-2 and R-3 of the D. rafinesquii species complex are given in the following 

 tables: Numbers of gill rakers (Table 21 ); correlated counts of AO photophores (Table 22); body 

 proportions for the four forms of the D./"i//^(?ns complex (Table 23); body proportions for the 

 three forms of the D. rafinesquii complex from the North Pacific Ocean and for D. rafinesquii 

 from the North Atlantic Ocean (Table 24). 



125 



