heterodontiform

Heterodontiform is an order of cartilaginous fishes belonging to the subclass Elasmobranchii. The most distinctive feature of heterodontiforms, which gives them their name, is the presence of two distinct types of teeth in their jaws. The anterior teeth are sharp and pointed, suitable for grasping prey, while the posterior teeth are molar-like and flattened, used for crushing. This heterodont dentition is unique among sharks. Currently, only one family, Heterodontidae, and one genus, Heterodontus, are recognized within this order. These sharks are commonly known as bullhead sharks due to their broad, flattened heads and the presence of prominent ridges above their eyes, which can resemble horns. They are generally small to medium-sized sharks, typically found in tropical and warm-temperate waters of the Pacific and Indian Oceans. Most species inhabit coral reefs and rocky bottoms, often lurking in crevices or caves during the day and becoming more active feeders at night. Their diet primarily consists of small invertebrates such as sea urchins, crustaceans, and mollusks, which they crush with their specialized posterior teeth. Heterodontiforms are oviparous, meaning they lay eggs. The eggs are typically large, spiral-shaped, and possess a tough outer shell, which the female deposits in sheltered locations. There are a limited number of recognized species within the Heterodontus genus, including the Port Jackson shark and the horn shark.