''Callionymus belcheri'', Belcher's dragonet or the flathead dragonet, is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

dragonet Dragonets are small, percomorph, marine fish of the diverse family Callionymidae (from the Greek ''kallis'', "beautiful" and ', "name") found mainly in the tropical waters of the western Indo-Pacific. They are benthic organisms, spending mos ...

native to the

Pacific Ocean The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the contin ...

waters off of Australia and

Papua New Guinea Papua New Guinea (abbreviated PNG; , ; tpi, Papua Niugini; ho, Papua Niu Gini), officially the Independent State of Papua New Guinea ( tpi, Independen Stet bilong Papua Niugini; ho, Independen Stet bilong Papua Niu Gini), is a country i ...

where it occurs at depths of from .

Description

''Callionymus belcheri'' has a yellowish to brown head and body with many small white spots on its back. The flanks are marked with white blotches which have dark brown margins. The underside is white. There are two

dorsal fin A dorsal fin is a fin located on the back of most marine and freshwater vertebrates within various taxa of the animal kingdom. Many species of animals possessing dorsal fins are not particularly closely related to each other, though through c ...

s, the first dorsal fin is brownish in colour, with a distal margin that is often blackish and which in males has white spots. The second dorsal fin is marked wither with light and dark streaks or with small white spots. The anal fin of males has a dark streak and in females is colourless or has dark spots on ots distal portion. The lower two-thirds of the

caudal fin Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as ...

has brown spots. The preopercular spine has a concave ventral margin. There are a total of 4 spines in the dorsal fins and 9 soft rays with 8 soft rays in the anal fin. This species grows to a length of SL.

Distribution

''Callionymus belcheri'' occurs in

Queensland ) , nickname = Sunshine State , image_map = Queensland in Australia.svg , map_caption = Location of Queensland in Australia , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , establishe ...

from

Moreton Bay Moreton Bay is a bay located on the eastern coast of Australia from central Brisbane, Queensland. It is one of Queensland's most important coastal resources. The waters of Moreton Bay are a popular destination for recreational anglers and are ...

north to northern

New Guinea New Guinea (; Hiri Motu: ''Niu Gini''; id, Papua, or , historically ) is the world's second-largest island with an area of . Located in Oceania in the southwestern Pacific Ocean, the island is separated from Australia by the wide Torr ...

and into the Gulf of Carpentaria, and westwards to northern

Western Australia Western Australia (commonly abbreviated as WA) is a state of Australia occupying the western percent of the land area of Australia excluding external territories. It is bounded by the Indian Ocean to the north and west, the Southern Ocean to th ...

Habitat and biology

''Callionymus belcheri'' is a marine, demersal fish which occurs at depth ranges of . It has a varied diet which is mainly made up of invertebrates including

polychaete Polychaeta () is a paraphyletic class of generally marine annelid worms, commonly called bristle worms or polychaetes (). Each body segment has a pair of fleshy protrusions called parapodia that bear many bristles, called chaetae, which are made ...

worms, gastropods, bivalves, small crustaceans and scaphopods. Larger fish also ate

echinoderm An echinoderm () is any member of the phylum Echinodermata (). The adults are recognisable by their (usually five-point) radial symmetry, and include starfish, brittle stars, sea urchins, sand dollars, and sea cucumbers, as well as the s ...

s and Caperllids. They appear to feed mainly in the late afternoon between 16:00 and 18:00, spending the rest of the day buried in sand or mud. This species spawns once a year in the southern Autumn, from March to May. They mature at lengths of in both sexes and females become less fertile towards the end of their lives.

Taxonomy and naming

The subspecies ''Callionymus belcheri recurvispinnis'', as named by Fricke. is regarded as a valid species by some authorities and is treated as such in FishBase, the authority used here for species of fish. The specific name honours the British Naval officer and explorer Admiral Sir

Edward Belcher Admiral Sir Edward Belcher (27 February 1799 – 18 March 1877) was a British naval officer, hydrographer, and explorer. Born in Nova Scotia, he was the great-grandson of Jonathan Belcher, who served as a colonial governor of Massachusett ...

(1799-1877) who collected many specimens during his career and was a collector of shells.

References

{{Taxonbar, from=Q521788 B Fish described in 1844