Scatophagidae, the scats are a small

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 ...

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 in the order

Perciformes Perciformes (), also called the Acanthopteri, is an order or superorder of ray-finned fish in the clade Percomorpha. ''Perciformes'' means " perch-like". Among the well-known members of this group are perches and darters ( Percidae), and als ...

. They are found in the

Indo-Pacific The Indo-Pacific is a vast biogeographic region of Earth. In a narrow sense, sometimes known as the Indo-West Pacific or Indo-Pacific Asia, it comprises the tropical waters of the Indian Ocean, the western and central Pacific Ocean, and the ...

region but one species has been introduced elsewhere.

Taxonomy

Scatophagidae was first formally described as a family in 1883 by the American ichthyologist Theodore Nicholas Gill. They are classified in the superfamily Siganiodea, along with the

rabbitfish Rabbitfishes or spinefoots, genus ''Siganus'', are perciform fishes in the family (biology), family Siganidae. It is the only Extant taxon, extant genus in its family and has 29 species. In some now obsolete classifications, the species having ...

es of the family

Siganidae Siganidae, the rabbitfishes, are a small family of ray-finned fishes in the order Perciformes. The only extant genus is '' Siganus'', the rabbitfish and spinefoot. However, a number of genera are known from fossils. The extant species are marine ...

, within the

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 ...

Percoidei Percoidei is a suborder of bony fishes in the order Perciformes. Many commercially harvested fish species are considered to be contained in this suborder, including the groupers, Serranidae, seabasses and perches. Divisions The following classif ...

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 ...

''. Other workers have classified them with the

surgeonfish Acanthuridae are a family (biology), family of ray-finned fish which includes surgeonfishes, tangs, and Naso (fish), unicornfishes. The family includes about 86 Extant taxon, extant species of ocean, marine fish living in tropical seas, usually ...

es in the order

Acanthuriformes Acanthuriformes is a large, diverse order of mostly marine ray-finned fishes, part of the Percomorpha clade. In the past, members of this clade were placed in the suborders Acanthuroidea and Percoidea of the order Perciformes, but this treatment ...

or as ''

incertae sedis or is a term used for a taxonomy (biology), taxonomic group where its broader relationships are unknown or undefined. Alternatively, such groups are frequently referred to as "enigmatic taxa". In the system of open nomenclature, uncertainty ...

'' within the series

Eupercaria Percomorpha () is an extremely large and diverse clade of ray-finned fish. With more than 17,000 known species (including tuna, seahorses, gobies, cichlids, flatfish, wrasse, perches, anglerfish, and pufferfish) known from both marine and fresh ...

. The name of the family comes from its

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 ...

''Scatophagus'' and this is a compound of ''skatos'' meaning "dung" and ''phaga'' which means to eat, a reference to its species' purported taste for human faeces.

Genera

There are two genera classified within the Scatophagidae, each containing two extant species: * '' Scatophagus''

Cuvier Jean Léopold Nicolas Frédéric, baron Cuvier (23 August 1769 – 13 May 1832), known as Georges Cuvier (; ), was a French natural history, naturalist and zoology, zoologist, sometimes referred to as the "founding father of paleontology". Cuv ...

, 1831 * '' Selenotoca''

Myers Myers as a surname has several possible origins, e.g. Old French ("physician"), Old English ("mayor"), and Old Norse ("marsh"). People * Abram F. Myers (1889–after 1960), chair of the Federal Trade Commission and later general counsel and b ...

, 1936

The fossil genus '' Eoscatophagus'' Tyler & Sorbini, 1999 (previously placed in ''Scatophagus'') is known from the

Early Eocene In the geologic timescale the Ypresian is the oldest age (geology), age or lowest stage (stratigraphy), stratigraphic stage of the Eocene. It spans the time between , is preceded by the Thanetian Age (part of the Paleocene) and is followed by th ...

of Italy, and represents the earliest record of the family. Also known from Italy is '' Oligoscatophagus'' Tyler & Sorbini, 1999 from the

Early Oligocene The Rupelian is, in the geologic timescale, the older of two age (geology), ages or the lower of two stage (stratigraphy), stages of the Oligocene epoch (geology), Epoch/series (stratigraphy), Series. It spans the time between . It is preceded b ...

. Both these fossil genera contain species that were initially described in the 19th century as members of ''Scatophagus''.Tyler, J.C. & Sorbini, C. 1999
Phylogeny of the fossil and recent genera of fishes of the family Scatophagidae (Squamipinnes)
Boll. Mus. Civ. Stor. Nat. Verona 23 : pages 353–393

Characteristics

Scatophagidae fishes, the scats, have highly compressed, oblong bodies. The dorsal profile of the head rises steeply to the nape, they have a rounded snout, as is the space between the eyes. The small mouth is horizontal, and cannot be protruded, and has several rows of small bristle-like teeth on the jaws. There are no teeth on the roof of the mouth. 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 ...

has 11–12 robust spines and 16–18 soft rays, the first spine lies flat and there is a deep incision between the spiny and soft-rayed parts of the fin. 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 ...

has 4 robust spines and 13–16 soft rays and the relatively small

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 have 16–17 rays. The

caudal 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 only ...

may be truncate or weakly emarginate. although it is rounded in juveniles. The head and the body are covered with tiny ctenoid scales and these reach the soft rayed parts of the dorsal and anal fins. There are no spines or serrations on the opercular bones. They are silvery or greenish in colour marked with darker spots or bars. The scats vary in maximum

total length Fish measurement is the measuring of individual fish and various parts of their anatomies, for data used in many areas of ichthyology, including taxonomy and fishery biology. Overall length Standard length (SL) is the length of a fish measured f ...

from for '' Selenotoca papuensis'' up to for '' Selenotoca multifasciata''.

Distribution and habitat

Scatophagidae is native to the Indian and Pacific Oceans from the eastern coast of Africa into the western Pacific. The spotted scat (''Scatophagus argus'') has been introduced to Malta, where it has become established, and it has been recorded from Florida. Scats are found in harbours, brackish estuaries, and the lower reaches of freshwater streams.

Biology

Scatophagidae fishes normally occur in schools and they feed during the day on a variety of benthic invertebrates, bottom

detritus In biology, detritus ( or ) is organic matter made up of the decomposition, decomposing remains of organisms and plants, and also of feces. Detritus usually hosts communities of microorganisms that colonize and decomposition, decompose (Reminera ...

, algae and refuse.

Utilisation

Scatophagidae fishes are too small to be of interest to commercial fisheries as food, they are caught using gill nets and fish traps. They appear in the aquarium trade.

References

* * {{Taxonbar, from=Q585021 Acanthuriformes families Extant Ypresian first appearances