130 Commercial Shark Fishing in the Caribbean Area 



Figure 47 



Family Eulamidae 



Genus Hypoprion, Xight Sharks. No spiracles; no longitudinal 

 ridges on the caudal penduncle ; mid-point of the base of the first 

 dorsal is at least as near to the axil (armpit) of the pectoral as 

 to the origin of the pelvics; no furrow on the lower jaw and only 

 a very short one on the upper; teeth with smooth edged cusps, 

 but the uppers with several coarse serrations or small denticles 

 toward the base on the outer side. 



Figure 47. Hypoprion signatus, Night Shark. 



Description: Trunk comparatively stout with a low but unmis- 

 takable ridge along the mid-line of the back between the two dor- 

 sal fins; the head noticeably long, occupying about 1/3 of the 

 length of the trunk to the origin of the caudal ; snout narrow and 

 rounded at tip; gill openings noticeably small and about as long as 

 the diameter of the eye ; anterior margin of the nostril with a well- 

 marked, narrow-triangular lobe near its inner end; upper teeth 

 narrow-triangular, increasingly oblique toward the corners of the 

 mouth and with their outer margins deeply notched ; lower teeth 

 more slender than uppers, symmetrical and nearly erect; second 

 dorsal fin a little less than 1/2 as long at the base as first dorsal 

 and relatively much lower; lower lobe of caudal about 2/5 as long 

 as upper lobe ; anal about as large as second dorsal but with much 

 more deeply concave rear margin ; pectoral about 2/3 as long as 

 head with weakly and evenly concave distal margin and narrowly 

 rounded corners. 



Color: Bluish gray above, sprinkled with small black spots; 

 grayish white below. 



Size: The few specimens so far measured have ranged from 

 about 38 inches to about 12 feet, 6 inches long. 



Habits: The only available information is that Cuban fisher- 

 men reported it as caught well off shore on set lines at depths greater 

 than 1 50 fathoms, and only at night. 



Range: So far known positively from stray specimens off South 

 Carolina and from the north coast of Cuba, where, however, it is so 

 common that thirty-six large ones have been landed at one time at the 

 Fishery Station at Cojimar. 



