Squalus acanthias

**Definition:** A species of shark in the family SQUALIDAE, used for its oil (SQUALENE) and as fish meal. It also figures heavily in biological research, especially with reference to its RECTAL GLAND in studies of WATER-ELECTROLYTE BALANCE.

**Tree numbers:** - B01.050.150.900.493.370.853.392.800.500

**Synonyms:** - Dogfish, Spiny