''Liocranium'' is a small

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 ...

of marine

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 ...

es,

waspfish Tetraroginae is a subfamily of marine ray-finned fishes, commonly known as waspfishes or sailback scorpionfishes, belonging to the family Scorpaenidae, the scorpionfishes and their relatives. These fishes are native to the Indian Ocean and the We ...

es belonging to the

subfamily In biological classification, a subfamily (Latin: ', plural ') is an auxiliary (intermediate) taxonomic rank, next below family but more inclusive than genus. Standard nomenclature rules end botanical subfamily names with "-oideae", and zo ...

Tetraroginae Tetraroginae is a subfamily of marine ray-finned fishes, commonly known as waspfishes or sailback scorpionfishes, belonging to the family Scorpaenidae, the scorpionfishes and their relatives. These fishes are native to the Indian Ocean and the ...

, which is

classified Classified may refer to: General *Classified information, material that a government body deems to be sensitive *Classified advertising or "classifieds" Music *Classified (rapper) (born 1977), Canadian rapper * The Classified, a 1980s American ro ...

as part of 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 ...

Scorpaenidae The Scorpaenidae (also known as scorpionfish) are a family (biology), family of mostly ocean, marine fish that includes many of the world's most venomous species. As their name suggests, scorpionfish have a type of "sting" in the form of sharp ...

, the scorpionfishes and their relatives. The fishes in this genus are found in the eastern

Indian Ocean The Indian Ocean is the third-largest of the world's five oceanic divisions, covering or approximately 20% of the water area of Earth#Surface, Earth's surface. It is bounded by Asia to the north, Africa to the west and Australia (continent), ...

and the western

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

Taxonomy

''Liocranium'' was first described as a genus in 1903 by the Australian

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 ...

James Douglas Ogilby James Douglas Ogilby (16 February 1853 – 11 August 1925) was an Australian ichthyologist and herpetologist. Ogilby was born in Belfast, Ireland, and was the son of zoologist William Ogilby and his wife Adelaide, née Douglas. He received ...

when he described a new species of waspfish from

Queensland Queensland ( , commonly abbreviated as Qld) is a States and territories of Australia, state in northeastern Australia, and is the second-largest and third-most populous state in Australia. It is bordered by the Northern Territory, South Austr ...

he called ''Liocranium praepositum'' and placed in a new

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 ...

genus. In 1927

Gilbert Percy Whitley Gilbert Percy Whitley (9 June 1903 – 18 July 1975) was a British-born Australian ichthyologist and malacologist who was curator of fishes at the Australian Museum in Sydney for about 40 years. Early life and education Gilbert Percy Whitley ...

proposed the name ''Abcichthys'' for this genus as he considered that ''Liocranium'' was preoccupied by the spider genus ''

Liocranum ''Liocranum'' is a genus of spiders in the family Liocranidae. The genus was first described by Ludwig Carl Christian Koch in 1866. Species According to ''The World Spider Catalog, Version 12.5'': * '' Liocranum apertum'' Denis, 1960 — France ...

'', however, there is enough difference between these two names to regard ''Liocranium'' as valid and Whitley's name is treated as 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 ...

. In 1964 Mees classified ''Paracentropogon pleurostigma'', which had been described by Weber from New Guinea, as a subspecies of ''L. praepositum'', ''L.p. pleurostigma''. It has subsequently been recognised as the second species in the genus ''Liocranium''. This taxon is included in the subfamily Tetraroginae within the Scorpaenidae in the 5th edition of ''

Fishes of the World ''Fishes of the World'' is a standard reference for the systematics of fishes. It was first written in 1976 by the American ichthyologist Joseph S. Nelson (1937–2011). Now in its fifth edition (2016), the work is a comprehensive overview of t ...

'' however other authorities place that subfamily within the stonefish family

Synanceiidae Synanceiinae is a subfamily of Venom, venomous ray-finned fishes, waspfishes, which is classification of life, classified as part of the family Scorpaenidae, the scorpionfishes and their relatives. These fishes are found in the Indo-Pacific ocean ...

, while other authorities classify this subfamily as a family in its own right. The genus name ''liocranium'' is a compound of ''leios'', meaning "smooth", and ''cranium'', which means "skull", presumed to refer to the head of ''L. praepositum'' which has no skin flaps or tentacles.

Species

''Liocranium'' has the following 2 species classified within it: * '' Liocranium pleurostigma'' (

Weber Weber may refer to: Places United States * Weber, Missouri, an unincorporated community * Weber City, Virginia, a town * Weber City, Fluvanna County, Virginia, an unincorporated community * Weber County, Utah * Weber Canyon, Utah * Weber R ...

, 1913) (western blackspot waspfish) * '' Liocranium praepositum'' Ogilby, 1903 (blackspot waspfish)

Characteristics

''Liocranium'' waspfishes are characterised by having the origin of 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 ...

being clearly in front of a vertical line running from the rear of the orbit. The dorsal fin is continuous with the front 3 spines not being nearly separate from the other 10. The dorsal fin contains 13 spines and 8, unfrequently 7 or 9, soft rays. There are 14, sometimes 13 or 15, fin rays in 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, 4 in the

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 and 5 or 6 in 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 ...

. There are no teeth on the

palatine bone In anatomy, the palatine bones (; derived from the Latin ''palatum'') are two irregular bones of the facial skeleton in many animal species, located above the uvula in the throat. Together with the maxilla, they comprise the hard palate. Stru ...

, There are many, small

cycloid scale A fish scale is a small rigid plate that grows out of the skin of a fish. The skin of most jawed fishes is covered with these protective scale (zoology), scales, which can also provide effective Underwater camouflage, camouflage through the us ...

s covering the flanks. The body has a depth which is 39–46% of its

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 ...

. These fishes attain a maximum total length of .

References

Tetraroginae Marine fish genera Taxa named by James Douglas Ogilby {{Scorpaeniformes-stub