1) Fish genus 2) Genus hexanchus 
The sixgill sharks, Hexanchus, are a genus of deepwater sharks in the family Hexanchidae. These sharks are characterized by broad pointed heads, six pairs of gill slits, comb-like, yellow lower teeth, and a long tail. It can grow up to 5 m (18 ft) long and weigh over 600 kg (1320 lb). They are abyssal plain scavengers with a keen sense of smell an...
[n] - a genus of Hexanchidae
genus Hexanchus noun a genus of Hexanchidae