The tasselled wobbegong (''Eucrossorhinus dasypogon'') is a

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

carpet shark Carpet sharks are sharks classified in the order (biology), order Orectolobiformes . Sometimes the common name "carpet shark" (given because many species resemble ornately patterned carpets) is used interchangeably with "wobbegong", which is the ...

in the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Orectolobidae and the only extant member of the

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

''Eucrossorhinus''. It inhabits shallow

coral reef A coral reef is an underwater ecosystem characterized by reef-building corals. Reefs are formed of colonies of coral polyps held together by calcium carbonate. Most coral reefs are built from stony corals, whose polyps cluster in group ...

s off northern

Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...

New Guinea New Guinea (; Hiri Motu: ''Niu Gini''; , fossilized , also known as Papua or historically ) is the List of islands by area, world's second-largest island, with an area of . Located in Melanesia in the southwestern Pacific Ocean, the island is ...

, and adjacent

island An island or isle is a piece of land, distinct from a continent, completely surrounded by water. There are continental islands, which were formed by being split from a continent by plate tectonics, and oceanic islands, which have never been ...

s. Reaching in length, this species has a broad and flattened body and head. Its most distinctive trait is a fringe of branching dermal flaps around its head, which extends onto its chin. The fringe, along with its complex color pattern of small blotches and reticulations, enable it to

camouflage Camouflage is the use of any combination of materials, coloration, or illumination for concealment, either by making animals or objects hard to see, or by disguising them as something else. Examples include the leopard's spotted coat, the b ...

itself against the reef environment. During the day, the solitary tasselled wobbegong can generally be found lying inside caves or under ledges with its tail curled. Individual sharks tend to remain within a local area and have favored resting spots. While resting, it opportunistically ambushes nearby

fish A fish (: fish or fishes) is an aquatic animal, aquatic, Anamniotes, anamniotic, gill-bearing vertebrate animal with swimming fish fin, fins and craniate, a hard skull, but lacking limb (anatomy), limbs with digit (anatomy), digits. Fish can ...

and

invertebrate Invertebrates are animals that neither develop nor retain a vertebral column (commonly known as a ''spine'' or ''backbone''), which evolved from the notochord. It is a paraphyletic grouping including all animals excluding the chordata, chordate s ...

s, and also lures in prey by waving its tail to mimic the appearance of a small fish. At night, it emerges and actively forages for food. This species is aplacental viviparous, though little is known of its life history. The tasselled wobbegong has been reported to bite and kill humans unprovoked, although such has only been reported once in 1940. The

International Union for Conservation of Nature The International Union for Conservation of Nature (IUCN) is an international organization working in the field of nature conservation and sustainable use of natural resources. Founded in 1948, IUCN has become the global authority on the stat ...

(IUCN) listed this species as

Near Threatened A near-threatened species is a species which has been Conservation status, categorized as "Near Threatened" (NT) by the International Union for Conservation of Nature (IUCN) as that may be vulnerable to Endangered species, endangerment in the ne ...

in 2003, as outside of Australia it is threatened by

fisheries Fishery can mean either the enterprise of raising or harvesting fish and other aquatic life or, more commonly, the site where such enterprise takes place ( a.k.a., fishing grounds). Commercial fisheries include wild fisheries and fish farm ...

and

habitat degradation Habitat destruction (also termed habitat loss or habitat reduction) occurs when a natural habitat is no longer able to support its native species. The organisms once living there have either moved elsewhere, or are dead, leading to a decrease ...

. As of 2015, its IUCN status is Least Concern.

Taxonomy and phylogeny

Dutch

ichthyologist Ichthyology is the branch of zoology devoted to the study of fish, including bony fish (Osteichthyes), cartilaginous fish (Chondrichthyes), and jawless fish (Agnatha). According to FishBase, 35,800 species of fish had been described as of March 2 ...

Pieter Bleeker Pieter Bleeker (10 July 1819 – 24 January 1878) was a Dutch medical doctor, Ichthyology, ichthyologist, and Herpetology, herpetologist. He was famous for the ''Atlas Ichthyologique des Indes Orientales Néêrlandaises'', his monumental work on ...

originally described the tasselled wobbegong in an 1867 volume of ''Archives Néerlandaises des Sciences Exactes et Naturelles''. His account was based on two

Indonesia Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania, between the Indian Ocean, Indian and Pacific Ocean, Pacific oceans. Comprising over List of islands of Indonesia, 17,000 islands, including Sumatra, ...

n specimens, one caught off Waigeo and the other off Aru. He gave it the name ''dasypogon'', from the

Greek Greek may refer to: Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group *Greek language, a branch of the Indo-European language family **Proto-Greek language, the assumed last common ancestor of all kno ...

''dasys'' ("hairy") and ''pogon'' ("beard"), and assigned it to the

''Crossorhinus'' (a

synonym A synonym is a word, morpheme, or phrase that means precisely or nearly the same as another word, morpheme, or phrase in a given language. For example, in the English language, the words ''begin'', ''start'', ''commence'', and ''initiate'' are a ...

of '' Orectolobus''). In 1908,

Charles Tate Regan Charles Tate Regan (1 February 1878 – 12 January 1943) was a British ichthyology, ichthyologist, working mainly around the beginning of the 20th century. He did extensive work on fish classification schemes. Born in Sherborne, Dorset, he was ...

created the new genus ''Eucrossorhinus'' for this species, derived from the Greek ''eu'' ("well"), ''krossoi'' ("tassel") and ''rhinos'' ("nose"). Regan subsequently reconsidered the main trait he used to separate ''Eucrossorhinus'' (the spacing of the fourth and fifth

gill slit Gill slits are individual openings to gills, i.e., multiple gill arches, which lack a single outer cover. Such gills are characteristic of cartilaginous fish such as sharks and rays, as well as deep-branching vertebrates such as lampreys. In c ...

s) and synonymized it with ''Orectolobus''. Later authors have placed the tasselled wobbegong either in its own genus or in ''Orectolobus''. Other

common name In biology, a common name of a taxon or organism (also known as a vernacular name, English name, colloquial name, country name, popular name, or farmer's name) is a name that is based on the normal language of everyday life; and is often con ...

s for this species are bearded wobbegong and Ogilby's wobbegong. Morphological studies have been inconclusive about the evolutionary relationships of the tasselled wobbegong, but overall have gauged it to be among the more derived wobbegong (Orectolobidae) species. A 2009

phylogenetic In biology, phylogenetics () is the study of the evolutionary history of life using observable characteristics of organisms (or genes), which is known as phylogenetic inference. It infers the relationship among organisms based on empirical dat ...

analysis based on

mitochondrial A mitochondrion () is an organelle found in the cells of most eukaryotes, such as animals, plants and fungi. Mitochondria have a double membrane structure and use aerobic respiration to generate adenosine triphosphate (ATP), which is used ...

and

nuclear DNA Nuclear DNA (nDNA), or nuclear deoxyribonucleic acid, is the DNA contained within each cell nucleus of a eukaryotic organism. It encodes for the majority of the genome in eukaryotes, with mitochondrial DNA and plastid DNA coding for the rest. ...

found otherwise, that this species was in fact basal to all other wobbegongs except the northern wobbegong (''O. wardi''). This result supports the synonymization of ''Eucrossorhinus'' with ''Orectolobus''.

Molecular clock The molecular clock is a figurative term for a technique that uses the mutation rate of biomolecules to deduce the time in prehistory when two or more life forms diverged. The biomolecular data used for such calculations are usually nucleot ...

estimation placed the

speciation Speciation is the evolutionary process by which populations evolve to become distinct species. The biologist Orator F. Cook coined the term in 1906 for cladogenesis, the splitting of lineages, as opposed to anagenesis, phyletic evolution within ...

of the tasselled wobbegong at 11–6 Ma, coinciding with a period of significant geological rearrangement and the formation of

habitats in the region.

Description

The tasselled wobbegong is a very broad, moderately flattened shark. The head is wider than long, with a distinctive fringe of branching dermal lobes running almost continuously from the snout tip to the origins of the

pectoral fin Fins are moving appendages protruding from the body of fish that interact with water to generate thrust and help the fish aquatic locomotion, swim. Apart from the tail or caudal fin, fish fins have no direct connection with the vertebral column ...

s, including a "beard" on the chin. The nostrils bear long, branching

barbels In fish anatomy and turtle anatomy, a barbel is a slender, whisker like sensory organ near the mouth (sometimes called whiskers or tendrils). Fish that have barbels include the catfish, the carp, the goatfish, the hagfish, the sturgeon, the z ...

, and have grooves surrounding them and connecting them to the mouth. There are

tubercle In anatomy, a tubercle (literally 'small tuber', Latin for 'lump') is any round nodule, small eminence, or warty outgrowth found on external or internal organs of a plant or an animal. In plants A tubercle is generally a wart-like projectio ...

s above the eyes but not elsewhere, and behind the eyes are larger spiracles. The large mouth is positioned ahead of the eyes, almost at the end of the head. There are furrows on the lower jaw extending from the mouth corners and along the jaw median. There are 23–26 upper and 19 lower tooth rows; each tooth has a single slender, pointed cusp. The three upper and two lower rows of symphysial (central) teeth are especially long and fang-like. The five pairs of gill slits are short. The pectoral and

pelvic fin Pelvic fins or ventral fins are paired fins located on the ventral (belly) surface of fish, and are the lower of the only two sets of paired fins (the other being the laterally positioned pectoral fins). The pelvic fins are homologous to the hi ...

s are large and rounded. The

dorsal fin A dorsal fin is a fin on the back of most marine and freshwater vertebrates. Dorsal fins have evolved independently several times through convergent evolution adapting to marine environments, so the fins are not all homologous. They are found ...

s are short-based and fairly tall; the first is slightly larger than the second and originates over the latter quarter of the pelvic fin bases. Behind the pelvic fins, the body rapidly tapers to the short

caudal peduncle Fins are moving appendages protruding from the body of fish that interact with water to generate thrust and help the fish swim. Apart from the tail or caudal fin, fish fins have no direct connection with the back bone and are supported only ...

. The

anal fin Fins are moving appendages protruding from the body of fish that interact with water to generate thrust and help the fish swim. Apart from the tail or caudal fin, fish fins have no direct connection with the back bone and are supported o ...

originates behind the midpoint of the second dorsal fin and is no more than half its size. The

caudal fin Fins are moving appendages protruding from the body of fish that interact with water to generate thrust and help the fish swim. Apart from the tail or caudal fin, fish fins have no direct connection with the back bone and are supported only ...

is short, with no lower lobe and an upper lobe bearing a strong ventral notch near the tip. This species has a

mosaic A mosaic () is a pattern or image made of small regular or irregular pieces of colored stone, glass or ceramic, held in place by plaster/Mortar (masonry), mortar, and covering a surface. Mosaics are often used as floor and wall decoration, and ...

-like dorsal color pattern consisting of numerous small, dark blotches and lines on a gray- or yellow-brown background; there may also be darker bands. The pattern extends to the underside of the tail and the ventral pectoral and pelvic fin margins. The ventral surface is otherwise white. The tasselled wobbegong is reliably known to reach a length of . Most authors consider an older record of a long individual to be erroneous.

Distribution and habitat

The range of the tasselled wobbegong encompasses the

continental shelf A continental shelf is a portion of a continent that is submerged under an area of relatively shallow water, known as a shelf sea. Much of these shelves were exposed by drops in sea level during glacial periods. The shelf surrounding an islan ...

of northern Australia from

Ningaloo Reef The Ningaloo Coast is a World Heritage Site located in the north west coastal region of Western Australia. The heritage-listed area is located approximately north of Perth, along the East Indian Ocean. The distinctive Ningaloo Reef that frin ...

in the west to

Bundaberg Bundaberg () is the major regional city in the Wide Bay-Burnett region of the state of Queensland, Australia. It is the List of cities in Australia by population, ninth largest city in the state. The Bundaberg central business district is situa ...

in the east, as well as

, Waigeo, and the Aru Islands. Additional records from

Malaysia Malaysia is a country in Southeast Asia. Featuring the Tanjung Piai, southernmost point of continental Eurasia, it is a federation, federal constitutional monarchy consisting of States and federal territories of Malaysia, 13 states and thre ...

are unconfirmed. This common bottom-dweller inhabits coral reefs, perhaps exclusively, in both inshore and offshore waters from the

intertidal zone The intertidal zone or foreshore is the area above water level at low tide and underwater at high tide; in other words, it is the part of the littoral zone within the tidal range. This area can include several types of habitats with various ...

to around deep. It is most often encountered in reef channels and faces, or atop

coral Corals are colonial marine invertebrates within the subphylum Anthozoa of the phylum Cnidaria. They typically form compact Colony (biology), colonies of many identical individual polyp (zoology), polyps. Coral species include the important Coral ...

heads.

Biology and ecology

Considered the most specialized member of its family, the tasselled wobbegong's ornate coloration and complex dermal fringe grants it excellent

, while it is probably a slower swimmer than related species. It is solitary and spends most of the day lying motionless inside caves or under ledges with its tail curled up. Individual sharks have a small

home range A home range is the area in which an animal lives and moves on a periodic basis. It is related to the concept of an animal's territory which is the area that is actively defended. The concept of a home range was introduced by W. H. Burt in 1943. ...

, containing several preferred resting spots that are used repeatedly. This species becomes more active at night, swimming onto the reef to hunt. The tasselled wobbegong feeds on bony and

cartilaginous fish Chondrichthyes (; ) is a class of jawed fish that contains the cartilaginous fish or chondrichthyans, which all have skeletons primarily composed of cartilage. They can be contrasted with the Osteichthyes or ''bony fish'', which have skeleto ...

es,

crustacean Crustaceans (from Latin meaning: "those with shells" or "crusted ones") are invertebrate animals that constitute one group of arthropods that are traditionally a part of the subphylum Crustacea (), a large, diverse group of mainly aquatic arthrop ...

s, and

cephalopod A cephalopod is any member of the molluscan Taxonomic rank, class Cephalopoda (Greek language, Greek plural , ; "head-feet") such as a squid, octopus, cuttlefish, or nautilus. These exclusively marine animals are characterized by bilateral symm ...

s. Its capacious mouth allows sizeable prey to be swallowed, with one documented case of a long individual consuming a long brownbanded bamboo shark (''Chiloscyllium punctatum''). During daytime, this species is an opportunistic

ambush predator Ambush predators or sit-and-wait predators are carnivorous animals that capture their prey via stealth, luring or by (typically instinctive) strategies utilizing an element of surprise. Unlike pursuit predators, who chase to capture prey u ...

. It preys upon schooling

nocturnal Nocturnality is a ethology, behavior in some non-human animals characterized by being active during the night and sleeping during the day. The common adjective is "nocturnal", versus diurnality, diurnal meaning the opposite. Nocturnal creatur ...

fishes such as

squirrelfish Holocentrinae is a subfamily of Holocentridae containing 40 recognized species and one proposed species. Its members are typically known as squirrelfish and all are nocturnal. All three genera in the subfamily are found in the Atlantic and ''Ho ...

es, soldierfishes, and sweepers that often shelter in the same cave. Tiny fishes and crustaceans have been seen settling atop the resting wobbegong's head, attracting larger fishes that are in turn attacked by the wobbegong. Observations in captivity have further revealed that this species seems to engage in active luring behavior. When it perceives food nearby, it begins to slowly wave its tail back and forth; its caudal fin resembles a small fish, complete with a dark eyespot at the base. The shark typically rests with its head elevated, which places it within striking distance of any prey drawn by its tail. The

tapeworm Eucestoda, commonly referred to as tapeworms, is the larger of the two subclasses of flatworms in the class Cestoda (the other subclass being Cestodaria). Larvae have six posterior hooks on the scolex (head), in contrast to the ten-hooked Ce ...

'' Parachristianella monomegacantha'' is a known

parasite Parasitism is a Symbiosis, close relationship between species, where one organism, the parasite, lives (at least some of the time) on or inside another organism, the Host (biology), host, causing it some harm, and is Adaptation, adapted str ...

of the tasselled wobbegong. This species has been observed being attended by

cleaner shrimp Cleaner shrimp is a common name for a number of swimming Decapoda, decapod crustaceans that clean other organisms of parasites. Most are found in the family (biology), families Hippolytidae (including the Pacific cleaner shrimp, ''Lysmata amboi ...

('' Leander urocaridella'', ''

Stenopus hispidus ''Stenopus hispidus'' is a shrimp-like decapod crustacean belonging to the infraorder Stenopodidea. Common names include coral banded shrimp and banded cleaner shrimp. Distribution ''Stenopus hispidus'' has a pan-tropical distribution, extendi ...

'') and bluestreak cleaner wrasse (''Labroides dimidiatus''). Reproduction is presumably aplacental viviparous like other wobbegongs, with the developing

embryo An embryo ( ) is the initial stage of development for a multicellular organism. In organisms that reproduce sexually, embryonic development is the part of the life cycle that begins just after fertilization of the female egg cell by the male sp ...

s sustained by

yolk Among animals which produce eggs, the yolk (; also known as the vitellus) is the nutrient-bearing portion of the egg whose primary function is to supply food for the development of the embryo. Some types of egg contain no yolk, for example bec ...

. There is a report of

mating In biology, mating is the pairing of either opposite-sex or hermaphroditic organisms for the purposes of sexual reproduction. ''Fertilization'' is the fusion of two gametes. '' Copulation'' is the union of the sex organs of two sexually repr ...

being observed inside a cave at night. Newborns measure approximately long. Size at

sexual maturity Sexual maturity is the capability of an organism to reproduce. In humans, it is related to both puberty and adulthood. ''Puberty'' is the biological process of sexual maturation, while ''adulthood'', the condition of being socially recognized ...

is uncertain; one recorded male was found to be adult at long.

Human interactions

With several records of apparently unprovoked attacks on people, the tasselled wobbegong has a reputation beyond other wobbegongs for aggressive behavior. Gilbert Whitley even wrote in 1940 that it "attacks and generally kills the natives" of

Papua New Guinea Papua New Guinea, officially the Independent State of Papua New Guinea, is an island country in Oceania that comprises the eastern half of the island of New Guinea and offshore islands in Melanesia, a region of the southwestern Pacific Ocean n ...

. Though Whitley's claim is questionable, this species is certainly capable of inflicting severe wounds. Conversely, the tasselled wobbegong is also an

ecotourism Ecotourism is a form of nature-oriented tourism intended to contribute to the Ecological conservation, conservation of the natural environment, generally defined as being minimally impactful, and including providing both contributions to conserv ...

attraction and many divers have approached it without incident. Given this shark's cryptic appearance and poor vision, humans should exercise caution to avoid accidentally harassing it or causing it to mistake a hand or foot for prey. This species adapts well to captivity and is occasionally found in the home aquarium trade. The tasselled wobbegong has little economic value, though its attractive skin is occasionally used for

leather Leather is a strong, flexible and durable material obtained from the tanning (leather), tanning, or chemical treatment, of animal skins and hides to prevent decay. The most common leathers come from cattle, sheep, goats, equine animals, buffal ...

. In Australian waters, it is not fished and faces minimal threats. However, elsewhere in its range it may be negatively affected by extensive fishery activity and

from

pollution Pollution is the introduction of contaminants into the natural environment that cause harm. Pollution can take the form of any substance (solid, liquid, or gas) or energy (such as radioactivity, heat, sound, or light). Pollutants, the component ...

blast fishing Blast fishing, fish bombing, dynamite fishing or grenade fishing is a destructive fishing practice using explosives to stun or kill schools of fish for easy collection. This often illegal practice is extremely destructive to the surrounding eco ...

, and coral removal. The

(IUCN) has assessed this species as

Least Concern A least-concern species is a species that has been evaluated and categorized by the International Union for Conservation of Nature (IUCN) as not being a focus of wildlife conservation because the specific species is still plentiful in the wil ...

References

External links

"''Eucrossorhinus dasypogon'', Tasselled wobbegong" at FishBase

"Biological Profiles: Tasselled Wobbegong" at Florida Museum of Natural History
* {{Taxonbar, from1=Q17283906, from2=Q29090, from3=Q107333145 Orectolobidae Fish described in 1867