Platycephaloidei is a

suborder Order () 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 recognized ...

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, part 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 ...

Scorpaeniformes The Scorpaeniformes are a diverse Order (biology), order of Actinopterygii, ray-finned fish, including the lionfishes and sculpins, but have also been called the Scleroparei. It is one of the five largest orders of bony fishes by number of spec ...

, and includes the flatheads,

ghost flathead ''Hoplichthys'', the ghost flatheads, is a genus of marine ray-finned fishes native to the Indian and Pacific Oceans. This genus is the only member of the family Hoplichthyidae. Taxonomy Hoplichthys was first proposed as a monotypic genus in 1 ...

s and

sea robin Prionotinae is a subfamily of demersal, marine ray-finned fishes, part of the family Triglidae. The fishes in this subfamily are called sea robins and are found in the Western Atlantic and Eastern Pacific Oceans, the other two Triglid subfamili ...

Taxonomy

Platycephaloidei was first recognised and named as a taxonomic grouping in 1943 by the Japanese

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 ...

Kiyomatsu Matsubara was a Japanese people, Japanese marine biologist, ichthyologist, and herpetologist. Born Kiyomatsu Sakamoto in Hyogo Prefecture, Kiyomatsu Matsubara was the first professor of the Department of Fisheries of the University of Kyoto and is consider ...

. 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 ...

'' classifies this group as a suborder within the Scorpaeniformes. Other authorities classify the families that make up Patycephaloidei in the 5th edition of ''Fishes of the World'' as two suborders; the Platycephaloidei, consisting of the families Bembridae, Parabembridae (separated from Bembridae), Platycephalidae, Hoplichthyidae and

Plectrogeniidae ''Plectrogenium'', is a genus of marine ray-finned fishes, the stinger flatheads, the only genus classified within the subfamily Plectrogeninae, which in turn is classified within the family Scorpaenidae. This genus is found in the Indian and Pa ...

(treated as a

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 ...

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 ...

in ''Fishes of the World'') and the Trigloidei, including the families Triglidae and Peristediidae. The name of the suborder is taken from that of the

type genus In biological taxonomy, the type genus (''genus typica'') is the genus which defines a biological family and the root of the family name. Zoological nomenclature According to the International Code of Zoological Nomenclature, "The name-bearin ...

Platycephalus ''Platycephalus'' is a genus of mostly marine, demersal ray-finned fish belonging to the family Platycephalidae. They are found in the eastern Mediterranean, the Indian Ocean and western Pacific Ocean. Taxonomy ''Platycephalus'' was first pro ...

'' which means "flat head".

Families and subfamilies

The following families and subfamilies are classified within the suborder Platycephaloidei: *

Triglidae ''Triglidae'', commonly known as gurnards or sea robins, are a Family (biology), family of bottom-feeding scorpaeniform ray-finned fish. The gurnards are distributed in temperate and tropical seas worldwide. Taxonomy ''Triglidae'' was first des ...

Rafinesque Constantine Samuel Rafinesque-Schmaltz (; 22 October 178318 September 1840) was a French early 19th-century polymath born near Constantinople in the Ottoman Empire and self-educated in France. He traveled as a young man in the United States, ult ...

, 1815 (Gurnards and sea robins) **

Prionotinae Prionotinae is a subfamily of demersal, marine ray-finned fishes, part of the family Triglidae. The fishes in this subfamily are called sea robins and are found in the Western Atlantic and Eastern Pacific Oceans, the other two Triglid subfamilies ...

Kaup, 1873 **

Pterygotriglinae Pterygotriglinae is a subfamily of demersal, marine ray-finned fishes, part of the family Triglidae, the gurnards and searobins. These gurnards are found in the Indo-Pacific region. Taxonomy Pterygotriglinae was first proposed as a taxonomic grou ...

Fowler, 1938 **

Triglinae Triglinae is a subfamily of demersal, marine ray-finned fishes, part of the family Triglidae, the gurnards and searobins. These gurnards are found in all the tropical and temperate oceans of the world except for the Western Atlantic Ocean. Taxono ...

Rafinesque, 1815 *

Peristediidae Peristediidae, the armored sea robins or armoured gurnards, is a Family (biology), family of Actinopterygii, ray-finned fishes belonging to the suborder Platycephaloidei in the Order (biology), order Scorpaeniformes. They are found in the deep wa ...

Jordan & Gilbert, 1883 (Armoured searobins) *

Bembridae Bembridae, the deep-water flatheads, are a family of bottom-dwelling ray-finned fishes. They are found in the Indian and western Pacific Oceans. Taxonomy Bembridae was first proposed as a family in 1873 by the German zoologist Johann Jakob Kaup ...

Kaup, 1873 (Deepwater flatheads) *

Platycephalidae The Platycephalidae are a Family (biology), family of marine ray-finned fish, most commonly referred to as flatheads. They are relatives of the lionfish, and belong to the order Perciformes. Taxonomy Platycephalidae was first proposed as a famil ...

Swainson, 1839 (Flatheads) *

Hoplichthyidae ''Hoplichthys'', the ghost flatheads, is a genus of marine ray-finned fishes native to the Indian and Pacific Oceans. This genus is the only member of the family Hoplichthyidae. Taxonomy Hoplichthys was first proposed as a monotypic genus in 1 ...

Kaup, 1873 (Ghost flatheads)

Characteristics

Platycephaloidei fishes are characterised by having elongate bodies with flattened heads which typically have ridges and spines. There are two separate

dorsal fins 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 i ...

, the pelvic fins are widely separated and have a single spine and typically 5 soft rays, although the pelvic fins of the genus ''

Hoplichthys ''Hoplichthys'', the ghost flatheads, is a genus of marine ray-finned fishes native to the Indian Ocean, Indian and Pacific Oceans. This genus is the only member of the family (biology), family Hoplichthyidae. Taxonomy Hoplichthys was first pro ...

'' has 3 soft rays. 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 ...

may contain 0, 1 or 3 spines and between 5 and 18 soft rays. They may or may not have a swimbladder. The flatheads of the family Platycephalidae are the largest fishes within this taxon with some attaining lengths of .

Distribution and habitat

Platycephaloidei fishes, in the sense of the alternative classification to that of ''Fishes of the World'' outlined under Taxonomy are not found in the New World and are found in the temperate and tropical waters where they are demersal fishes found from relatively shallow inshore waters to moderate depths of around in offshore waters. The Trigloidei are more widely distributed and are also demersal fishes occurring on the

continental shelf A continental shelf is a portion of a continent that is submerged under an area of relatively shallow water, known as a shelf sea. Much of these shelves were exposed by drops in sea level during glacial periods. The shelf surrounding an islan ...

on sand or mud substrates.

Fisheries

Platycephaloidei fishes are utilised by fisheries, some species of sea robins are of commercial importance and some flatheads are important food fishes, particularly in Australia.

References

{{Taxonbar, from=Q2098835 Taxa named by Kiyomatsu Matsubara Scorpaenoidei