''Congrogadus'' is a

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 ...

ray-finned fishes Actinopterygii (; ), members of which are known as ray-finned fish or actinopterygians, is a class (biology), class of Osteichthyes, bony fish that comprise over 50% of living vertebrate species. They are so called because of their lightly built ...

, the type genus of 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 ...

Congrogadinae Congrogadinae is a subfamily of ray-finned fishes, one of four subfamilies that make up the family Pseudochromidae, these elongated fish are commonly called eel-blennies. Characteristics The species in the subfamily Congrogadidae have elongated ...

, the eel blennies, part of the

dottyback The dottybacks are a family, Pseudochromidae, of fishes which were formerly classified in the order Perciformes or considered ''incertae sedis'' percomorphs, but are now considered basal blenniiforms. Around 152 species belong to this family. ...

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 ...

, Pseudochromidae. The genus ''Congrogadus'' has an

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 ...

distribution.

Characteristics

The species in the genus ''Congrogadus'' differ from their other genera in the subfamily Congogadinae in that they do not have a spot on their shoulder, a similar spot being located on the operculum. Their

dorsal Dorsal (from Latin ''dorsum'' ‘back’) may refer to: * Dorsal (anatomy), an anatomical term of location referring to the back or upper side of an organism or parts of an organism * Dorsal, positioned on top of an aircraft's fuselage The fus ...

and

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 ...

s have a higher number of rays than all the other species in the subfamily except for the species in the genus '' Halidesmus'' which can have up to 90 fin rays. Also compared to the related genera which may have three complete

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 epithelia ...

s, the species in ''Congrogadus'' have only have a single curtailed lateral line. In addition some species which are classified in the

subgenus In biology, a subgenus ( subgenera) is a taxonomic rank directly below genus. In the International Code of Zoological Nomenclature, a subgeneric name can be used independently or included in a species name, in parentheses, placed between the ge ...

''Congrogadoides'' have the gill membranes fused to the isthmus. The gill membranes of the subgenus ''Congrogadus'' are not fused while the species in that subgenus and in the third, ''Pilbaraichthys'' possess a posterior otic sensory canal pore, which is believed to assist the fish in detecting motion.

Biology

''Congrogadus'' are secretive fish which hide among rocks and coral rubble and they occur from the surface down to . They feed mainly on crustaceans but larger specimens will take fish, and their large mouth enable them to swallow quite large prey. Most species of the subfamily are

protogynous hermaphrodites Sequential hermaphroditism (called dichogamy in botany) is one of the two types of hermaphroditism, the other type being simultaneous hermaphroditism. It occurs when the organism's sex changes at some point in its life. A sequential hermaphrodite ...

but ''Congrogadus subducens'' appears to be different because the females greater than long have been observed to have small

gonads A gonad, sex gland, or reproductive gland is a mixed gland and sex organ that produces the gametes and sex hormones of an organism. Female reproductive cells are egg cells, and male reproductive cells are sperm. The male gonad, the testicle, ...

, a feature which almost certainly means that they are not protogynous hermaphrodites. All of this subfamily lay eggs in a small clump. The eggs of species within ''Congragadus'' are a distinguishing feature of the genus as each egg is attached to a small hook which has a thin thread. When the egg mass begins to disintegrate the hook falls from the egg to be suspended underneath it by the thread. It is thought this allows the egg to attach itself to the substrate.

Distribution

The genus is found in the Indian Ocean and the western Pacific Ocean and some species have rather restricted distributions while ''c. subducens'' has been claimed over a wide distribution from northern Australia through the

Malay Archipelago The Malay Archipelago is the archipelago between Mainland Southeast Asia and Australia, and is also called Insulindia or the Indo-Australian Archipelago. The name was taken from the 19th-century European concept of a Malay race, later based ...

to Japan, although other sources state that it is endemic to Australia.

Species

The following species are classified as members of the genus ''Congrogadus'': * Subgenus ''Congrogadoides'' ** '' Congrogadus amplimaculatus'' ( Winterbottom, 1980) (Largespot eel blenny) ** '' Congrogadus malayanus'' (

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 ...

, 1909) (Malayan eel blenny) ** '' Congrogadus spinifer'' (Borodin, 1933) (Spiny eel blenny) * Subgenus ''Congradadus'' ** '' Congrogadus hierichthys'' D.S. Jordan & R.E. Richardson, 1908 (Sulu eel blenny) ** '' Congrogadus subducens'' (Richardson, 1843) (Carpet eel-blenny) * Subgenus ''Pilbaraichthys'' ** '' Congrogadus winterbottomi'' A.C. Gill, Mooi & Hutchins, 2000 (Pilbara eelblenny)

References

{{Taxonbar, From=Q2486714 Congrogadinae Taxa named by Albert Günther