Latin name

Eucrossorhinus dasypogon

Other name

Eucrossorhinus dasypogon

Identification

The Tasselled Wobbegong has a flattened and broad head and body. The width of the head exceeds its length and is 11% of the total length. The head is covered from the tip of the snout to the base of the pectoral fins by a continuous fringe of skin scales, including a "beard" on the chin. The nostrils are framed by long, branched antennae and surrounded by grooves that connect them to the mouth. There are tubercles above the eyes and superior spiracles behind the eyes. The large mouth is in front of the eyes and extends almost to the end of the snout. The lower jaw is dotted with furrows running from the corners of the mouth to the middle. There are 23-26 upper and 19 lower rows of teeth in the mouth. Each tooth ends in a thin tip. The three upper and three lower rows of symphyseal teeth are particularly long and shaped like fangs. There are 5 pairs of short gill slits.

Features of fish fins

The width of the body at the base of the pectoral fins is approximately equal to the length of the head. The pectoral and ventral fins are very large, broad and rounded. The distance between the beginning of the bases of the pectoral and pelvic fins is equal to the length of the base of the pectoral fins and less than the distance between the bases and free tips of the pelvic fins. The dorsal fins are rather high with short bases. There are no spines at their bases. The first dorsal fin is slightly larger than the second. Its base begins at the level of the last quarter of the base of the pelvic fins. The height of the first dorsal fin is approximately equal to the length of its base, which is less than the length of the pelvic fins. The distance between the dorsal fins exceeds the length of the inner edge of the first dorsal fin and is slightly more than ½ of its base. Behind the pelvic fins, the body tapers sharply into a short tail peduncle. The distance from the beginning of the base of the pelvic fins to the base of the caudal fin is almost equal to the length of the head. The base of the anal fin begins at the level of the midpoint of the base of the second dorsal fin. The anal fin is 2 times smaller than the second dorsal fin. The caudal fin is short, asymmetrical, with a large ventral notch at the edge of the upper lobe, and the lower lobe is undeveloped. 

Fish colouring

The colouration of the tasselled wobbegong is a mosaic of numerous small dark patches scattered over a grey or yellow-brown background, sometimes with dark bars. This pattern extends to the ventral surface of the caudal fin and the edges of the pectoral and pelvic fins. The rest of the body is white. 

Distribution

Widespread off the north coast of Australia from Ningaloo Reef in the west to Bundaberg in the east, as well as off New Guinea and the Waigeo and Aru Islands. Additional data on the presence of this species in Malaysian waters has not been officially confirmed. 

Habitat

These common bottom-dwelling sharks are found on the continental shelf and inhabit coral reefs from the surf zone to depths of around 50 metres.

Size

The maximum length of a male of this species is 366 cm, the usual length is 180 cm. 

Behavior

These aulas, which are probably the slowest swimmers of their kind, are well camouflaged by their colourful plumage and abundant skin fringe. They live solitary lives, spending most of the day lying motionless in caves or under reefs with their tails curled in a semicircle. They have a limited individual home range with several frequently used hiding places. Despite their low activity during the day, they are able to hunt from ambush, luring prey with undulating movements of their fish-like tail. At night they become more active and swim out onto the reef to hunt.

Food and feeding habits

Their diet consists of bony and cartilaginous fish, crustaceans and cephalopods. Their large mouth allows them to swallow large prey, with one documented case of a 1.3m fish eating a metre-long brown-tipped Asian shark. During the day, tasselled wobbegongs are opportunistic, sneaky predators. They prey on gregarious nocturnal fish, often hiding with them in the same shelters. Tiny fish and crustaceans settle on their heads, attracting larger fish that become their prey. Observations of wobbegongs in captivity have shown that they actively lure prey. When they detect an attractive object nearby, they begin to slowly wag their tail from side to side. The wobbegonga's tail resembles that of a small fish, the resemblance being accentuated by the dark eye spot at the base. Sharks usually rest with their head raised and are able to grab any prey that comes close to their tail with a single stroke.

Reproduction

This species appears to reproduce by oviparity. They have been observed mating at night in a cave. The offspring were about 20 cm long. The adult male was 1.2 m long.

Fishing

The species is not of interest to commercial fisheries, although the mottled skin is prized and used for leather. These sharks are not caught in Australian waters. 

Relationship with a person

Traumatogenic. Several unprovoked attacks on humans by carpet wobbegongs have been recorded and this species is considered the most aggressive of the wobbegongs. Despite the potential danger, this species is attractive for ecotourism and divers approach these sharks without consequence. Due to their camouflaging colouration and poor eyesight, humans should handle them with caution. They do well in captivity and are sometimes sold for home aquariums.