Latin name

Hemiscyllium ocellatum

Other names

Hemiscyllium ocellatum

Identification

There is no hood on the head from the snout to the gills. The mouth is in front of the eyes. Sharks have an elongated body, more than half of which is on the caudal peduncle. The snout is short and rounded. The nostrils are located at the tip of the snout and are framed by antennae. There are grooves between the nostrils and the mouth. There are 26-35 upper and 21-32 lower rows of teeth in the mouth. The teeth are small, with broad bases and triangular cusps. The oval eyes are located dorsolaterally on the head. Behind the eyes, there are splashing.  The gill slits are small, with the fourth and fifth gills close together. Epaulette sharks can survive for over 3 hours at 5% atmospheric oxygen without loss of behavioral responses. 

Features of fish fins

Pectoral and ventral fins are thick and muscular. Spines at the base of the dorsal fins are absent. Dorsal fins of equal size, set back. The base of the first dorsal fin is posterior to the base of the pelvic fins. The caudal peduncle is very long. The long anal fin is immediately anterior to the caudal fin. The caudal fin is asymmetrical, elongated, with a ventral notch on the edge of the upper lobe, the lower lobe is undeveloped.

Fish colouring

The ventral surface of the head is uniformly pale in adult sharks. The preorbital area is unmarked. Black "epaulettes" above the pectoral fins are large, in the form of "eyes" edged in white. The posterior half of the main pattern is surrounded by chaotically scattered small spots. There are no white spots on the fins or body. The body is covered with large and small markings that form a complex network. The pectoral and pelvic fins have a thin white border. The body of juvenile sharks is covered with alternating light and dark saddle-shaped markings. Their coloration serves as protective camouflage, and "epaulets" above the pectoral fins confuse predators. 

Distribution

They inhabit the Pacific Ocean from the southern coast of New Guinea to the northern coast of Australia as far north as Sydney. There are unconfirmed reports of their presence in the waters of Malaysia, Sumatra and the Solomon Islands.

Habitat

These sharks are found in shallow waters no deeper than 50 meters, sometimes with the water barely covering their backs. They prefer tide pools and coral reefs.

Size

Epaulette shark length up to 1.07 m. Weight up to 3 kg.

Behavior

Swimming in shallow water is impossible, so the shark crawls by bending its body from side to side and resting on its paddle-shaped pectoral and pelvic fins. Compared to other sharks, the cartilaginous framework of these fins is reduced and divided, making them more flexible and allowing them to move like limbs. Because of this mode of locomotion, these sharks are even able to crawl across land from one tide pool to another. Their "gait" is similar to that of four-legged animals such as salamanders, and it is likely that such movements, necessary for walking on land, preceded and accelerated the evolution of the first terrestrial vertebrates.

Epaulette sharks are nocturnal. During the day, they often hide in crevices and under coral, only needing to cover their heads with water while the rest of their bodies remain in the air. Sometimes they position themselves with their head raised in the open or on top of the reef, head against the current, this form of orientation is known as rheotaxis, it improves breathing and helps hunting.

Food and feeding habits

Epaulette sharks feed in small bodies of water inundated by the tide. They are adaptable predators that prey on a variety of bottom-dwelling crustaceans, worms, and bony fish. Sharks are most active at sunset and dusk, although feeding does not stop during the day. Sharks locate prey primarily by olfaction and electroreception. They can suck in prey by stretching the muscles of their mouths. In search of food, sharks may turn over coral fragments or bury their snouts in sand, pushing sand out through their gill slits. Unlike most sharks, these sharks can chew their food for 5-10 minutes. Their teeth can sink down to form a flat surface that grinds up hard shells and clams.

Reproduction

Mating occurs from July to December, although they are capable of breeding throughout the year. Mating may be initiated by the female chasing the male and biting him. The male then grabs the female's pectoral fin with his teeth, lies down beside her, and inserts one of his pterygopodia into her cloaca. Copulation takes about 1.5 minutes. Females lay hard-shelled eggs from August to December, 2 per clutch. Clutches repeat every 14 days. A female lays 20-50 eggs per year. The egg capsule is 10 cm long and 4 cm wide. Newborns, 14-16 cm long, hatch from the eggs after 120-130 days. Their growth rate is slow at first, but increases to 5 cm per year after 3 months. Males and females reach sexual maturity at a length of 54-64 cm, which corresponds to an age of about 7 years. These sharks can live up to 20-25 years.

Fishing

Eyetooth catsharks are occasionally caught as bycatch in commercial and recreational fisheries.

Relationship with a person

Epaulette sharks are not dangerous to humans, but may bite if touched. 

The species is easy to keep in captivity and can be seen in many public aquariums in the United States, Canada and Australia.