The flathead congoli (''Halaphritis platcephala'') is a

species In biology, a species is the basic unit of 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 the appropriate s ...

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 hor ...

, belonging to the

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

Bovichtidae Bovichtidae, the temperate icefishes or thornfishes, is a family of marine ray-finned fishes, classified in the suborder Notothenioidei of the order Perciformes. They are native to coastal waters off Australia, New Zealand, and South America. ...

, the thornfishes or temperate icefishes. It is native to the seas off southeastern Australia. This species is the only known member of its

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

Taxonomy

The flathead congoli was first formally described in 2002 by Peter R. Last,

Arkady Vladimirovich Balushkin Arkady (russian: Арка́дий, Arkadiy) is a Slavic masculine given name, ultimately derived from the Greek name Αρκάδιος, meaning “from Arcadia”. The Latin equivalent is Arcadius. Notable people with the name include: People: *Ark ...

and

J. Barry Hutchins ''J. The Jewish News of Northern California'', formerly known as ''Jweekly'', is a weekly print newspaper in Northern California, with its online edition updated daily. It is owned and operated by San Francisco Jewish Community Publications In ...

with the type locality given as

Port Davey Port Davey is an oceanic inlet located in the south west region of Tasmania, Australia. Port Davey was named in honour of Thomas Davey, a former Governor of Tasmania. Port Davey is contained within the Port Davey/Bathurst Harbour Marine Natur ...

Tasmania ) , nickname = , image_map = Tasmania in Australia.svg , map_caption = Location of Tasmania in AustraliaCoordinates: , subdivision_type = Country , subdi ...

. It is the only species in the

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 ''Halaphritis''. The name of the genus ''Halaphritis'' is a compound of ''halos'' meaning "sea" and ''aphritis'' which is a name which dates back to

Aristotle Aristotle (; grc-gre, Ἀριστοτέλης ''Aristotélēs'', ; 384–322 BC) was a Greek philosopher and polymath during the Classical period in Ancient Greece. Taught by Plato, he was the founder of the Peripatetic school of phil ...

, who used it for a type of

anchovy An anchovy is a small, common forage fish of the family Engraulidae. Most species are found in marine waters, but several will enter brackish water, and some in South America are restricted to fresh water. More than 140 species are placed in 1 ...

whitebait Whitebait is a collective term for the immature fry of fish, typically between long. Such young fish often travel together in schools along coasts, and move into estuaries and sometimes up rivers where they can be easily caught using fine-m ...

, but the authors used as an allusion to ''

Pseudaphritis The congoli (''Pseudaphritis urvillii''), also known as the freshwater flathead, marble fish, marbled flathead, sand trout, sanding, sandy, sandy whiting or tupong. is a species of marine ray-finned fish and it is the only species of fish in t ...

'', emphasising this species marine habitat compared to the superficially similar congoli (''Pseudaphritis urvillii''), a predominantly fresh and brackish water species. The specific name ''platycephala'' means "flat head" alluding to the flattened head of this species.

Description

The flathead congoli has a flattened, elongate and shallow body, its depth being around 15% 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 m ...

. The head is quite large having its length being around 31% of the standard length and is highly flattened and has a wide rounded snout. The large eyes are close to each other and are on the back of the head. The mouth is large and terminal and there are small bristle-like teeth arranged in bands in each jaw. There is a small, weak, flattened spine on the operculum near the upper edge. The head and body, as well as the caudal and pectoral fins are covered in small ctenoid scales. The

lateral line The lateral line, also called the lateral line organ (LLO), is a system of sensory organs found in fish, used to detect movement, vibration, and pressure gradients in the surrounding water. The sensory ability is achieved via modified epithelial ...

is straight and clearly visible. The first dorsal fin has 9 spines is small with a short base with its origin just in front of the origin of 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 and the second dorsal fin has a base which is around three times the length of first. 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 se ...

contains 23 soft rays, has a long base and is similar in shape and sits opposite the second dorsal fin, although it is positioned slightly to its rear, The caudal fin is slightly rounded. The pectoral fins are large and rounded. 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 en ...

s ait at the jugular and are approximately arrow-shaped with the central fin rays being the longest. The maximum recorded

total 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 ...

was . The overall colour is dusky shading to paler ventrally with around five wide vague darkish bands along the back and flanks while the fins have pale margins.

Distribution and habitat

The flathead congoli is endemic to southeastern Australia where it is found around Tasmania and off

Wilsons Promontory Wilsons Promontory, is a peninsula that forms the southernmost part of the Australian mainland, located in the state of Victoria. South Point at is the southernmost tip of Wilsons Promontory and hence of mainland Australia. Located at nearb ...

Victoria Victoria most commonly refers to: * Victoria (Australia), a state of the Commonwealth of Australia * Victoria, British Columbia, provincial capital of British Columbia, Canada * Victoria (mythology), Roman goddess of Victory * Victoria, Seychelle ...

. It is found on shallow, semi-exposed reefs where it sheltersbelow ledges and deep within caves during the day.

Biology

The flathead congoli appears to be adapted for crawling around the substrate in confined spaces. Captive specimens have been observed to crawl over the substrate in preference to swimming. They have been fed on shrimps and other small crustaceans in captivity.

References

{{Taxonbar, from=Q2673400 Bovichtidae Monotypic fish genera Fish described in 2002