Family Myctophidae 



12. Lampanyctus beringensis Schmidt (Fig. 2) 



Lampanyctus beringensis Schmidt, Copeia, 1933, no. 3, p. 131 (Bering 

 Id., intermediate depth 93 fathoms) 



During the deep water stations of the DALNEVOSTOTCHNIK (1932) off Cape 

 Olytorsky seven examples of this interesting bathypelagic form were taken at 

 depths to 3000 m. Our material came from a Sigsby trawl and non -closing 

 plankton net. They are considerably damaged and only four could be used in 

 preparing the description. However, we must note the deformation is due to 

 sharp changes in pressure which is explained by the abnormal position of 

 eyes and internal organs and also due to the mechanical action of hauling 

 through 2-3 km of water when raising the nets. 



Our examples are closest to Lampanyctus nannochir (Gilbert), and only 

 a few slight differences in photophore position make us temporarily identify 

 it with L . beringensis described a short time ago by P . Y . Shmidt . 



D 14-15, A 15-16, P 8, V 8, G 18-20, upper procurrent caudal rays 

 6-7, lower 7-8. LI 37-38. R. br. 6. 



The body is relatively long and compressed; its greatest depth 16.7- 

 19.3 percent of the standard length. The caudal peduncle is long and does 

 not taper 25.9-28.4%. Gaudal peduncle depth 7.2-9. 1%. The head is large 

 and abruptly narrows from the nape to the snout, length 25.9-27.3%. Eye large, 

 its diameter 5.9-7.4%, about 4 in head. Interorbital broad and flat, 12-18%, 

 its length is divided dorsally by a thin pariillel ridge which is interrupted 

 in the middle by a lig^tbump (possibly a light organ?). A. similar formation 

 is found on the end of the snout between the premaxillary. There are two short 

 ridges behind the eye. Over the eye is an orbital shelf of cartilage . It is 

 hard in adults but spongy in the young (54-60 mm SL). The large mouth is 

 corneal. The border of the upper jaw is formed by the premaxillaries which 

 extend almost to the front of the preopercle, 17.6-20.5% SL or about 3/4 the 

 head. The lower jaw does not protrude, its proximal edge extending to the 

 subopercular and forming the lower angle of the head. Its length is 18 .8-21 .7% 

 SL or about 4/5 the head. Small, very fine hair like teeth occur on the pre- 

 maiillary, dentary, vomer and palatines, the pseudobranch is developed. Gill 

 rakers fine and numerous . 



Body covered with fine deciduous scales which are in six to seven longi- 

 tudinal rows. Head naked. Scales of LI not enlarged, with a double channel . 

 Predor sal 43.2-45.0%, preanal 53.4-55.6%, preventral 36.4-39.2%. 



