Diaphus mollis 



Taning, 1928 



Fig. 118 — Diaphus mollis, male, 55.4 mm. From about 27° N, 155" W. (Photophers retouched). 



Description 



D. 12-13; A. 12-13; P. 10-11; AO 5 (4-6) + 4 (3-5), total 9 (10); gill rakers 5-6 + 1 + 12-13 

 (11), total 18-19 (17-20); vertebrae 33. Numbers of gill rakers (Table 21) and AO photophores 

 (Table 22) are compared with counts for Forms A, B, C, and D of the Diaphus fulgens species 

 complex and for Forms R-1, R-2, and R-3 of the D. rafinesquii species complex of the Pacific 

 Ocean. 



Posterodorsal margin of operculum sharply angulate and recurved. Origin of dorsal fin 

 about over pelvic origin. Origin of anal fin behind a vertical from end of dorsal base by about 

 0.75% of the orbital diameter. End of base of adipose fin usually slightly before, occasionally 

 on, a vertical from end of anal base. Pelvic fins extend past anal origin by nearly the length of 

 the pupil in undamaged specimens. 



Body photophores rather small, often indistinct against the very dark integument nor- 

 mally found on freshly preserved and undamaged specimens. PLO on or very slightly behind a 

 vertical from origin of pectoral fin and above that origin by 39% (35-43% of the distance from it 

 to lateral line. VLO over bases of inner pelvic rays and nearer them by 45% (42-50% ) of the 

 distance to lateral line. VO2.3 interspace 53% (44-64% ) of the space between VLO and VO2 

 SAO3, Pol, and Prc4 lie about three of their respective diameters below lateral line. SAO series 

 broadly angulate, a line through SAOi.^ passing through or a little before VO.-, and well behind 

 SAO3. SAO^-:! interspace 2.0 to 2.5 times that of SAO,.-. First AOa elevated nearly to level of 

 SAO2 and from 1.5 to 2.0 times its diameter above second AOa. Last AOa seldom elevated by 

 more than its diameter above next to last AOa. Pol about over base of last anal ray. Pre 

 interspaces progressively wider. 



Vn of males much enlarged and in two parts; a large anterior part of dense, fine-grained 

 tissue, roughly triangular in shape, fills the space between anteroventral orbital margin, 

 premaxillary and nasal apparatus. The posterior part is much smaller and oblong; it appears 

 as a reflective layer thinly covered with luminous tissue; two parts are separated by a promi- 

 nent darkly pigmented streak. The luminous tissue of both parts is easily eroded and lost. The 

 small So barely intrudes into the orbital margin. Vn of females slender, elongate, entire, and 

 also easily lost. Luminous scale at PLO small, two to three times the size of that organ; it is 

 thin and weakly formed, the tissue appearing as granular or convoluted. 



Size: To about 65 mm. 



Least depth of capture: D. mollis has been dipnetted once in central Pacific waters; the 

 least depth of tows taking the species is from to 300 m. 



Distribution: Probably common in warmer waters of Pacific Ocean. I have seen specimens 

 from only one locality of the Indo-Pacific region, south of Mindanao, Philippines (Fig. 119). 



129 



