Form A may be related to Diaphus parri Taning (1932) primarily because of the lack of a 

 luminous scale at PLO, although Taning stated "PLO with a very diminutive luminous scale, 

 sometimes not to be seen." This scale was not discussed or illustrated by Nafpaktitis ( 1973 ) in 

 his redescription of Z). parri. The slight elevation of the first AOa is also similar in Form A and 

 in D. parri, but apparently this organ has a consistently higher position in Form A. Nafpak- 

 titis (1973) described the first AOaof D. parri as being very slightly, if at all, raised, whereas 

 in Form A it is at least a half, often a full, diameter above the level of the second AOa. The 

 numbers of AO photophores and gill rakers are very similar in both species. 



Forms B and D do not readily conform to any known species, or it may be that inadequate 

 data on variation in characters is available for a known related species. The very low numbers 

 of gill rakers of Form B, totalling 14 (13-15) is to my knowledge the lowest of any diaphid 

 species other than the quite unrelated D. problematicus Parr ( 1928). Form D differs from the 

 other three forms primarily in the very steeply slanting, almost vertical lines of the tissue in 

 the large luminous scale at PLO, a structure unlike that of any other diaphid species I have 

 seen. 



Two other species, Diaphus aliciae and D. kendalli, described by Fowler (1934) from near 

 the Philippines, should also be compared with the Forms A, B, C, and D, and with the ful- 

 gens" of Brauer. However, because of Fowler's inadequate descriptions and illustrations, com- 

 parisons are difficult, but the patterns of the SAO series of Fowlers two species are similar to 

 these forms and to that of fulgens, as delineated by Brauer. 



Both D. aliciae and D. kendalli are described and figured as having a large Vn. D. aliciae 

 is shown to have a large luminous scale at PLO, but D. kendalli is not; this apparent lack of 

 luminous scale at PLO is a character shared with Form A, but the latter appears to be a much 

 smaller species. Fowler reported a length of 69 mm for the holotype of Z). kendalli, but I found 

 the length to be 59.5 mm SL; both lengths are far in excess of the maximum length found for 

 the diminutive Form A (31 mm). Also, the numbers of gill rakers for D. kendalli are much 

 higher(6 + 1+ 13) than that of Form A (4 + 1 + 10(9-11) ). Fowler recorded 8 + 14rakersfor 

 D. kendalli. 



Diaphus aliciae and Form C may be conspecific, primarily because of a similarity in 

 numbers of gill rakers and sizes of luminous scales at PLO. I found the gill raker count for the 

 holotype of D. aliciae to be 6 -t- 1 -(- 12 plus 1 "nub" on lower limb, but Fowler recorded 7 + 17. 

 Fowler also reported a length of 53 mm, but I found it to be 42.0 mm SL. 



I have related Forms R-1, R-2, and R-3 to the Atlantic Ocean species Diaphus raflnesquii 

 (Cocco, 1838) rather than to the D. fulgens complex, because of several similarities. First, the 

 expanded Vn of males and the So organ are very close together, occasionally confluent; this 

 condition is not found in the D. fulgens group. Also, AO photophores (Table 22) and body 

 proportions (Table 24) are very similar. Nafpaktitis (1968) listed the number of gill rakers for 

 D. raftnesquii as 7-8 + 1 + 14-15, total 22-24, a count very similar to those of the three Pacific 

 forms (Table 21), although the latter have somewhat higher counts. Also, they attain a similar 

 size (70 to 94 mm), although these Pacific forms may reach a larger size than D. rafinesquii. 

 Becker (1967) recorded a specimen of 79.5 mm, the largest I have found recorded in the 

 literature, and much larger than the Forms of the Diaphus fulgens complex. 



Although quite alike in counts and superficial aspect, D. rafinesquii is distinct from these 

 Pacific forms in having a somewhat smaller and differently shaped enlarged Vn in males. Also, 

 the SAO series is straight or but very slightly angulate in D. rafinesquii , and a line through 

 the anterior margins of SAO, and SAO- touches or passes very near the posterior margin of 

 SAO3; in the Pacific forms this condition is approached only in Form R-1. 



Forms R-1, R-2, and R-3 are also basically similar to Diaphus theta Eigenmann and 

 Eigenmann ( 1890) and may occur sympatrically. However, D. theta is easily separable because 

 of the very low position of the first AOa, usually on the level of adjacent the AOA or, rarely, 

 elevated above that level by more than its diameter, usually only half Also, the SAO series is 

 almost evenly spaced and in a straight line in D. theta, whereas the SAO2-3 interspace is 

 always notably greater than that of SAO1.2 in the three forms in question. 



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