Oxynotus
Oxynotus is a genus of dogfish sharks belonging to the family Oxynotidae. Commonly referred to as “roughsharks” or “spiny dogfish”, these sharks are distinguished by their distinctive, rough skin covered in numerous, sharp, pointed denticles. The genus comprises seven recognized species found in the Atlantic and Indo-Pacific oceans, inhabiting deep waters from the continental shelf to the upper slope. Oxynotus sharks are generally small to medium in size, with the largest species reaching approximately 1.5 meters (5 feet) in length. They are characterized by their elongated, flattened bodies, large heads, and prominent, spiny fins, particularly the dorsal fins, which are armed with sharp, venomous spines.
Common Names
Oxynotus sharks are commonly known as "roughsharks" or "spiny dogfish". This nomenclature reflects their distinctive, rough skin texture and the prominent spines on their dorsal fins.
Characteristics
Oxynotus sharks possess several notable characteristics that distinguish them from other sharks:
- Rough Skin: Their skin is covered in numerous, sharp, pointed denticles, giving it a rough, sandpaper-like texture.
- Spiny Fins: Both dorsal fins are armed with sharp, venomous spines. These spines are used for defense and can inflict painful wounds.
- Elongated Body: Oxynotus sharks have an elongated, flattened body, resembling a flattened, elongated torpedo.
- Large Head: Their head is relatively large and broad, with a short, blunt snout.
- Small Mouth: The mouth is small and positioned on the underside of the head.
- Teeth: Their teeth are small, pointed, and arranged in multiple rows.
Environment
Oxynotus sharks are found in deep waters from the continental shelf to the upper slope, typically at depths of 200 to 1,000 meters (650 to 3,300 feet). They prefer areas with rocky bottoms and strong currents.