The large-headed whiting, ''Sillago megacephalus'', is a dubious

species In biology, a species is the basic unit of Taxonomy (biology), 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 ...

of coastal

marine Marine is an adjective meaning of or pertaining to the sea or ocean. Marine or marines may refer to: Ocean * Maritime (disambiguation) * Marine art * Marine biology * Marine debris * Marine habitats * Marine life * Marine pollution Military * ...

fish in the

smelt-whiting The Sillaginidae, commonly known as the smelt-whitings, whitings, sillaginids, sand borers and sand-smelts, are a family of benthic coastal marine fish in the order Perciformes. The smelt-whitings inhabit a wide region covering much of the Indo-P ...

family that has only been recorded from one

specimen Specimen may refer to: Science and technology * Sample (material), a limited quantity of something which is intended to be similar to and represent a larger amount * Biological specimen or biospecimen, an organic specimen held by a biorepository ...

captured off the coast of China in 1933. Although very similar to ''

Sillago sihama The northern whiting (''Sillago sihama''), also known as the silver whiting and sand smelt, is a marine fish, the most widespread and abundant member of the smelt-whiting family Sillaginidae. The northern whiting was the first species of sillagin ...

'', the species is characterised by an unusually large head which accounts for 33% of the total body length.

Taxonomy and naming

The large-headed whiting is one of 29

in the

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial n ...

Sillago ''Sillago'' is a genus of fish in the family Sillaginidae and the only non-monotypic genus in the family. Distinguishing the species can be difficult, with many similar in appearance and colour, forcing the use of swim bladder morphology as a de ...

'', which is one of three divisions of the smelt whiting family

Sillaginidae The Sillaginidae, commonly known as the smelt-whitings, whitings, sillaginids, sand borers and sand-smelts, are a family of benthic coastal marine fish in the order Perciformes. The smelt-whitings inhabit a wide region covering much of the Indo ...

. The smelt-whitings are

Perciformes Perciformes (), also called the Percomorpha or Acanthopteri, is an order or superorder of ray-finned fish. If considered a single order, they are the most numerous order of vertebrates, containing about 41% of all bony fish. Perciformes means ...

in the

suborder Order ( la, ordo) is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between family and class. In biological classification, the order is a taxonomic rank used in the classification of organisms and ...

Percoidei Percoidei is one of 3 suborders of bony fishes in the order Perciformes. Many commercially harvested fish species are considered to be contained in this suborder, including the snappers, groupers, basses, goatfishes and perches. Divisions Th ...

. The only specimen of the species ever recorded was taken from Paoping Harbour in

Hainan Hainan (, ; ) is the smallest and southernmost province of the People's Republic of China (PRC), consisting of various islands in the South China Sea. , the largest and most populous island in China,The island of Taiwan, which is slight ...

, China in 1933. Lin recorded the new species, designating the only sample to be the

holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of seve ...

of the species. In preparation of a 1985 review of the sillaginids, Roland McKay was unable to locate the holotype and has presumed it to be lost. McKay noted that based on its description, all features except an unusually large head where characteristic of the common species ''

'', suggesting the ''S. megacephalus'' is actually a junior synonym of ''S. sihama''. The common name of 'large-headed whiting' is a straight translation from its

binomial name In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...

, signifying the diagnostic head length.

Description

As already noted, the large-headed whiting is very similar to ''Sillago sihama'', but has a

head A head is the part of an organism which usually includes the ears, brain, forehead, cheeks, chin, eyes, nose, and mouth, each of which aid in various sensory functions such as sight, hearing, smell, and taste. Some very simple animals may no ...

length which is 33% of the body length, compared to the 27-30% observed in ''S. sihama''. The first

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 ...

has 11 spines, while the second dorsal fin has a single spine and 22

soft rays Fish anatomy is the study of the form or Morphology (biology), morphology of fish. It can be contrasted with fish physiology, which is the study of how the component parts of fish function together in the living fish. In practice, fish anatomy ...

. The

anal 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 s ...

is similar with two spines and 23 soft rays. There are about 70 lateral line scales. The

colour Color (American English) or colour (British English) is the visual perceptual property deriving from the spectrum of light interacting with the photoreceptor cells of the eyes. Color categories and physical specifications of color are associ ...

is uniform all over the body, with only the tip of the spinous dorsal fins black. Little else is known, including

swimbladder The swim bladder, gas bladder, fish maw, or air bladder is an internal gas-filled organ that contributes to the ability of many bony fish (but not cartilaginous fish) to control their buoyancy, and thus to stay at their current water depth w ...

morphology and

vertebrae The spinal column, a defining synapomorphy shared by nearly all vertebrates, Hagfish are believed to have secondarily lost their spinal column is a moderately flexible series of vertebrae (singular vertebra), each constituting a characteristi ...

numbers. The specimen described was 158 mm in length.

Distribution and habitat

The only known specimen of large-headed whiting was taken from

Taiwan Taiwan, officially the Republic of China (ROC), is a country in East Asia, at the junction of the East and South China Seas in the northwestern Pacific Ocean, with the People's Republic of China (PRC) to the northwest, Japan to the northe ...

ese waters, with no other records known of, and no information of the

habitat In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical ...

or depth the species lives at available. Aspects of the species

biology Biology is the scientific study of life. It is a natural science with a broad scope but has several unifying themes that tie it together as a single, coherent field. For instance, all organisms are made up of cells that process hereditar ...

and importance to fisheries are completely unknown at the present.

References

External links

Large-headed whiting at Fishbase
{{Taxonbar, from=Q1987100 Sillaginidae Taxa named by Lin Shu-Yen Fish described in 1933