The sharpnose sevengill shark has a narrow head with large eyes. Photo © George Burgess
It has seven pairs of gill slits in contrast to the five gills most sharks possess. This gill opening extends down to the throat. There is only one small dorsal fin originating from the inner margins of the pelvic fins. The front edge of the dorsal fin is straight or slightly convex, while the apex is rounded and the rear edge concave. The anal fin is also small in size with nearly straight edges, originating below the posterior end of the dorsal base. The pectoral fin is small with a weakly convex outer margin and a narrow rounded apex. The caudal axis is slightly raised with a convex upper margin and a subterminal notch on the lower margin. (Compagno 2001)
The sharpnose sevengill may be confused with the broadnose sevengill (Notorynchus cepedianus). The broadnose sevengill has small eyes and a broad, rounded snout in contrast to the large eyes and narrow, pointed mexico email list snout of the sharpnose sevengill. The broadnose sevengill also has black spots all over its body in contrast to the sharpnose sevengill which lacks this coloration. (Compagno 2001)
Dorsal and caudal fin placement of sharpnose sevengill shark. Photo © George Burgess
Dorsal and caudal fin placement of sharpnose sharks. Photo © George Burgess
Coloration
Brownish grey to olive on dorsal surface, pale to lighter ventral surface. Adults may have indistinct pale posterior margins on all fins, as well as faint dark spots on the body (Compagno 2001). Living specimens have large fluorescent green eyes. Juveniles may have dark spots on the flank area, as well as dark tips on the dorsal and caudal fins (Last and Stevens 2009).