92 Commercial Shark Fishing in the Caribbean Area 



Figure 30 



Family Hexanchidae, Six and Seven-Gilled Sharks. Six or 

 seven gill openings; an anal fin but only one dorsal fin; upper 

 and lower teeth noticeably unlike. 



Genus Heptranchias, Seven-Gilled Sharks. Seven gill openings, 

 otherwise much like Hexanchus (Figure 31). 



Figure 30. Heptianchias perlo, Seven-Gilled Shark. 



Description: Resembles the Six-Gilled Shark in general ap- 

 pearance, in relative sizes and locations of fins and in teeth (see 

 description under Figure 31). It differs sharply from it, however, 

 in having seven gill openings. Further differences are that its 

 snout is narrow and tapering, that the far edge of its pectoral 

 fin is noticeably concave and that its anal fin is much smaller than 

 its dorsal. 



Color: Gray, sometimes shaded with brown; only a little paler 

 below than above. The pectorals and the lower margin of the 

 caudal are bordered with white. The dorsal has two white spots 

 and is black at the tip. 



Size: Rorn at length of about 10 inches, it matures at 2 to 3 

 feet (males smaller than females) and grows to a maximum size 

 of about 7 feet. 



Habits: Little is known of its habits, except that it feeds on 

 smaller fish and that it lives chiefly on the bottom or near it. It 

 has been taken only in deep water in the Caribbean and off Portu- 

 gal, but also in shoal water off West Africa. 



Range: Both sides of the North Atlantic, Cape of Good Hope, 

 Japan, and perhaps Australia. In the Caribbean region it has been 

 recorded only off Matanzas, Cuba, where it is taken occasionally 

 by the long-line fishery in deep water. We include it to facilitate 

 identification, for it may probably prove widespead in the Carib- 

 bean in the deeper layers of water. 



