2a. VLO about midway between pelvic origin and lateral line. Gill rakers 



4 + 1 + 10 {Near L. gemellarii) 



VLO markedly nearer pelvic base than to lateral line. Gill rakers 5 + 1 + 12-14 3 



Pol about midway between lateral line and anal base, usually lower. SAO series straight 

 or slightly curved, the convexity directed anterodorsally. Pre evenly spaced, the last some- 

 times a little displaced posteriorly; Prc:,.4 interspace always less than that between 



Pre,.., L. gemellarii 



Pol nearer lateral line than to anal base, the distance between the two two to two and 

 one-half times that between Pol and lateral line. SAO in a gentle arc, the convexity 

 directed posteroventrally. Prc3.4 interspace large, usually greater than, or at least equal to, 

 that between Pre,.,-, L. dofleini 



2b 

 3a 



3h 



LobJanchia urolampa 



(Gilbert and Cramer, 1897) 



Fig. 79 — Lobianchia urolampa , male, 84.0 mm. 



Description 



D. 15; A. 15; P. 14-15; AO 7 -h 6; gill rakers 6 -I- 1 + 13-14, total 20-21; vertebrae 35 (5 

 specimens). 



L. urolampa is readily distinguished from other species of the genus by the high positions 

 of the PLO, VLO, SAO:,, and Pol, all at or near lateral line. Other equally distinctive charac- 

 ters are the high and nearly equally elevated VOj and VO3, the highly elevated first and last 

 AOa, and the presence (apparently) of but 2 SAO. None of these characters are present in any 

 other known species o{ Lobianchia. 



Supracaudal luminous gland rather short, filling half, or slightly more, of upper surface of 

 caudal peduncle; this gland is shorter and much less robust than those of L. gemellarii or L. 

 dofleini; the 5 to 7 individual luminous scales are poorly defined and not delimited by lines of 

 pigment in the five males (69-87 mm) before me. I have seen no females and can offer no 

 information concerning infracaudal luminous glands. 



L. urolampa was originally figured as having only 2 SAO, but Fraser-Brunner (1949) 

 figured 3. On the 10 sides before me there are but 2 SAO (Fig. 79). The first is almost directly 

 over VO.^ and a little less than midway between there and lateral line; the second is at lateral 

 line and slightly behind a line through V0-, and SAO,. Gilbert and Cramer (1897, PI. 38, fig. 1) 

 show this configuration, but in the text (p. 408) stated "Supraanals 3, forming nearly a right- 

 angled triangle, with one of the spots above the hindmost ventral spot, the second immediately 

 below the lateral line, and the third nearly above the first anterior anal spot." Such a configu- 

 ration as these authors described is unknown in the family Myctophidae, and it would seem 

 more reasonable to consider the posterior "spot" as an elevated AOa rather than a posteriorly 

 displaced SAO. 



94 



