|Family||Scientific Name||Author||Year||Common Name|
|Somniosidae||Somniosus microcephalus||(Bloch and Schneider)||1801||Greenland Shark|
Family Somniosidae — Head with 5 gill slits, all anterior to pectoral fins, the fifth not abruptly longer than the others. Eyes on sides of head, without nictitating eyelids. Spiracles always present, large and just behind eyes. Two dorsal fins with or without spines on their anterior margins, when present spines grooved, usually small, and on both dorsal fins. No anal fin.
Unique Characters: Length to 6.4 meters. Uniform dark gray, blackish, brownish, or ashy. Snout short, blunt. Eyes and spiracle small. Gill slits, low and short. Dorsal and pelvic fins small, similar in size. Pectoral fins small.
Similar Species: Portuguese Shark Centroscymnus coelolepis. Length to slightly more than 1.2 meters. Uniform blackish brown. Snout short, blunt. Eye large. Gill slits low and short. Dorsal fins small, almost equal in size, with a small spine. Pectoral fins small.