''Liocranium'' is a small

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 ...

of marine

ray-finned fish Actinopterygii (; ), members of which are known as ray-finned fishes, is a class of bony fish. They comprise over 50% of living vertebrate species. The ray-finned fishes are so called because their fins are webs of skin supported by bony or h ...

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 W ...

es belonging to the subfamily

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 W ...

, 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 roc ...

as part of the

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Scorpaenidae The Scorpaenidae (also known as scorpionfish) are a family of mostly 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 spines coated with venom ...

, 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 ~19.8% of the water on Earth's surface. It is bounded by Asia to the north, Africa to the west and Australia to the east. To the south it is bounded by ...

and the western

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 contine ...

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, 33,400 species of fish had been described as of October ...

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 ) , 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 , established_ ...

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 "unispec ...

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. He was born at Swaythling, Southampton, England ...

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 synomym. 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'' by the American Ichthyology, ichthyologist Joseph S. Nelson (1937–2011) is a standard reference for fish systematics. Now in its fifth edition (2016), the work is a comprehensive overview of the diversity and classificat ...

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

Synanceiidae Synanceiinae is a subfamily of venomous ray-finned fishes, waspfishes, which is classified as part of the family Scorpaenidae, the scorpionfishes and their relatives. These fishes are found in the Indo-Pacific oceans. They are primarily marine ...

, while other authorities classify this subfamily as a family in its own right. The genus name ''liocranium'' is a compund 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 ''Liocranium'' is a small genus of marine ray-finned fishes, waspfishes belonging to the subfamily Tetraroginae, which is classified as part of the family Scorpaenidae, the scorpionfishes and their relatives. The fishes in this genus are foun ...

'' ( Weber, 1913) (western blackspot waspfish) * ''

Liocranium praepositum ''Liocranium'' is a small genus of marine ray-finned fishes, waspfishes belonging to the subfamily Tetraroginae, which is classification of life, classified as part of the Family (biology), family Scorpaenidae, the scorpionfishes and their relati ...

'' Ogilby, 1903 (blackspot waspfish)

Characteristics

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

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 ...

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 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, 4 in the

pelvic fin Pelvic fins or ventral fins are paired fins located on the ventral surface of fish. The paired pelvic fins are homologous to the hindlimbs of tetrapods. Structure and function Structure In actinopterygians, the pelvic fin consists of two e ...

s and 5 or 6 in 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 ...

. There are no teeth on the

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

, 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 scales, which can also provide effective camouflage through the use of reflection and colouration, as w ...

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 their anatomies. These data are used in many areas of ichthyology, including taxonomy and fisheries biology. Overall length * Standard length (SL) is the length of a fish ...

. These fishes attain a maximum total length of .

References

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