The tubemouth (''Siphonognathus argyrophanes'') is a species of

ray-finned fish Actinopterygii (; ), members of which are known as ray-finned fish or actinopterygians, is a class of bony fish that comprise over 50% of living vertebrate species. They are so called because of their lightly built fins made of webbings of sk ...

, a weed whiting from 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 ...

Labridae. It is

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

to the southern coatsts of Australia where it is camouflaged to live among beds of seagrass.

Description

The tubemouth has a highly elongated head and body and has a fleshy barbel which protrudes from the end of the upper lip. It has many teeth fused into a beak-like structure. The long-based

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 ...

is low and the shorter

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 ...

sits below the posterior third of the dorsal fin. It has a long and pointed

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 ...

but lacks

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. It is green on the back, whitish to red-brown ventrally and has a dark stripe along the flanks. It can attain a

standard length Fish measurement is the measuring of individual fish and various parts of fish anatomy, their anatomies, for data used in many areas of ichthyology, including Taxonomy (biology), taxonomy and fishery biology. Overall length Standard length (SL) is ...

of .

Distribution

The tubemouth is endemic to southern Australia where it can be found from

Geraldton Geraldton (Wajarri language, Wajarri: ''Jambinu'', Wilunyu language, Wilunyu: ''Jambinbirri'') is a coastal city in the Mid West (Western Australia), Mid West region of Western Australia, north of the state capital, Perth. As of the , Geraldt ...

Western Australia Western Australia (WA) is the westernmost state of Australia. It is bounded by the Indian Ocean to the north and west, the Southern Ocean to the south, the Northern Territory to the north-east, and South Australia to the south-east. Western Aust ...

southwards and then along the southern coast of Australia to the

Gippsland Lakes The Gippsland Lakes are a network of coastal lakes, marshes and lagoons in East Gippsland, Victoria, Australia covering an overall area of about between the rural towns of Lakes Entrance, Bairnsdale and Sale. The largest of the lakes are ...

Victoria Victoria most commonly refers to: * Queen Victoria (1819–1901), Queen of the United Kingdom and Empress of India * Victoria (state), a state of Australia * Victoria, British Columbia, Canada, a provincial capital * Victoria, Seychelles, the capi ...

and

Tasmania Tasmania (; palawa kani: ''Lutruwita'') is an island States and territories of Australia, state of Australia. It is located to the south of the Mainland Australia, Australian mainland, and is separated from it by the Bass Strait. The sta ...

Habitat and biology

The tubemouth occurs in sheltered areas where there is a dense growth of ''

Posidonia ''Posidonia'' is a genus of flowering plants. It contains nine species of marine plants ("seagrass"), found in the seas of the Mediterranean and around the south coast of Australia. The APG system (1998) and APG II system (2003) accept this ge ...

'' sea grass, no deeper than . There is no known difference between the sexes and the biology of this species is almost unknown.

Taxonomy

The tubemouth closely resembles the

cornetfish The cornetfishes or flutemouths are a small family, the Fistulariidae, of extremely elongated fish in the order Syngnathiformes. The family consists of a single genus, ''Fistularia'', with four species, found worldwide in tropical and subtropical ...

es and

trumpetfish The trumpetfishes are three species of highly specialized, tubularly-elongated marine fishes in the genus ''Aulostomus'', of the monogeneric family Aulostomidae. The trumpetfishes are members of the order Syngnathiformes, together with the Syngn ...

es of the

order Order, ORDER or Orders may refer to: * A socio-political or established or existing order, e.g. World order, Ancien Regime, Pax Britannica * Categorization, the process in which ideas and objects are recognized, differentiated, and understood ...

Syngnathiformes The Syngnathiformes are an order of ray-finned fishes that includes the leafy seadragons, sea moths, trumpetfishes and seahorses, among others.FishBase (2005)Order Summary for Syngnathiformes Version of 2005-FEB-15. Retrieved 19 Aug 2008. Th ...

in body shape and form, this is an example of

convergent evolution Convergent evolution is the independent evolution of similar features in species of different periods or epochs in time. Convergent evolution creates analogous structures that have similar form or function but were not present in the last comm ...

. It species is apparently so unique in its form that, at first, it was described within the

Fistulariidae The cornetfishes or flutemouths are a small family, the Fistulariidae, of extremely elongated fish in the order Syngnathiformes. The family consists of a single genus, ''Fistularia'', with four species, found worldwide in tropical and subtropical ...

prior to being classified in its own

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unisp ...

family. The extremely slender body and highly elongated snout, are apparent in other members of the genus ''

Siphonognathus ''Siphonognathus'' is a genus of ray-finned fishes, weed whitings in the family Odacidae which are endemic to Southern Australian coastal waters. These fish are characterized by their extremely elongate bodies and live primarily in seagrass bed ...

'', these features, in combination with the lack of pelvic fins, possession of a barbel on the upper lip and extraordinarily high counts of

vertebrae Each vertebra (: vertebrae) is an irregular bone with a complex structure composed of bone and some hyaline cartilage, that make up the vertebral column or spine, of vertebrates. The proportions of the vertebrae differ according to their spinal ...

, fin rays and

lateral-line The lateral line, also called the lateral line organ (LLO), is a system of sensory organs found in fish, used to detect movement, vibration, and pressure gradients in the surrounding water. The sensory ability is achieved via modified epithelial ...

scales make it very different from its congeners. Although

Fishbase FishBase is a global species database of fish species (specifically finfish). It is the largest and most extensively accessed online database on adult finfish on the web.

places six species within the genus ''Siphonognathus'', the

Catalog of Fishes Catalog of Fishes is a comprehensive on-line database and reference work on the scientific names of fish species and genera. It is global in its scope and is hosted by the California Academy of Sciences. It has been compiled and is continuously up ...

places four of those species in the separate genus '' Sheardichthys'' and places the fifth on the

monospecific In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispe ...

genus '' Parodax'', leaving ''Siphonognathus'' as a monospecific genus containing only ''S. argyrophanes''.

References

{{Taxonbar, from=Q5236480 Labridae Fish described in 1858 Taxa named by John Richardson (naturalist)