Ricefish
Encyclopedia
The ricefishes are a family
(Adrianichthyidae) of small ray-finned fish that are found in fresh and brackish waters from India
to Japan
and out into the Indo-Australian Archipelago
, most notably Sulawesi
. The common name of the group derives from the fact that many species are found in Japanese rice paddies. About 27 species, some extremely rare and endangered, and some 2-4 may already be extinct.
. The largest species, the Buntingi
, is 20 centimetres (7.9 in) in length, but most are less than a fifth this length, with the smallest being only 1.7 centimetre (0.669291338582677 in) long. They have a number of distinctive features, including an unusual structure to the jaw, and the presence of an additional bone in the tail.
As with most fish, ricefish typically spawn their eggs, which are fertilised externally. However, some species, including the medaka, are known to fertilise the eggs internally, carrying them inside the body as the embryo develops. The female then lays the eggs just before they hatch. Several other species carry their eggs attached to the body between their pelvic fins.
The medaka, Oryzias latipes
, is a popular model organism
used in research in developmental biology
.
Genetic study of the family suggests that it originally evolved on Sulawesi and spread from there to the Asian mainland; the supposed genus Xenopoecilus are apparently unrelated, morphologically divergent species of Oryzias.
Family Adrianichthyidae
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
(Adrianichthyidae) of small ray-finned fish that are found in fresh and brackish waters from India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
to Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
and out into the Indo-Australian Archipelago
Malay Archipelago
The Malay Archipelago refers to the archipelago between mainland Southeastern Asia and Australia. The name was derived from the anachronistic concept of a Malay race....
, most notably Sulawesi
Sulawesi
Sulawesi is one of the four larger Sunda Islands of Indonesia and is situated between Borneo and the Maluku Islands. In Indonesia, only Sumatra, Borneo, and Papua are larger in territory, and only Java and Sumatra have larger Indonesian populations.- Etymology :The Portuguese were the first to...
. The common name of the group derives from the fact that many species are found in Japanese rice paddies. About 27 species, some extremely rare and endangered, and some 2-4 may already be extinct.
Description
Most of these species are quite small, making them of interest for aquariaAquarium
An aquarium is a vivarium consisting of at least one transparent side in which water-dwelling plants or animals are kept. Fishkeepers use aquaria to keep fish, invertebrates, amphibians, marine mammals, turtles, and aquatic plants...
. The largest species, the Buntingi
Buntingi
The buntingi or sharp-jawed buntingi is a species of fish in the Adrianichthyidae family. It is endemic to Indonesia.-References:...
, is 20 centimetres (7.9 in) in length, but most are less than a fifth this length, with the smallest being only 1.7 centimetre (0.669291338582677 in) long. They have a number of distinctive features, including an unusual structure to the jaw, and the presence of an additional bone in the tail.
As with most fish, ricefish typically spawn their eggs, which are fertilised externally. However, some species, including the medaka, are known to fertilise the eggs internally, carrying them inside the body as the embryo develops. The female then lays the eggs just before they hatch. Several other species carry their eggs attached to the body between their pelvic fins.
The medaka, Oryzias latipes
Oryzias latipes
Oryzias latipes, also known as Medaka and Japanese killifish, is a member of genus Oryzias , the only genus in the subfamily Oryziinae. This rather small...
, is a popular model organism
Model organism
A model organism is a non-human species that is extensively studied to understand particular biological phenomena, with the expectation that discoveries made in the organism model will provide insight into the workings of other organisms. Model organisms are in vivo models and are widely used to...
used in research in developmental biology
Developmental biology
Developmental biology is the study of the process by which organisms grow and develop. Modern developmental biology studies the genetic control of cell growth, differentiation and "morphogenesis", which is the process that gives rise to tissues, organs and anatomy.- Related fields of study...
.
Genetic study of the family suggests that it originally evolved on Sulawesi and spread from there to the Asian mainland; the supposed genus Xenopoecilus are apparently unrelated, morphologically divergent species of Oryzias.
Classification
As currently defined, the ricefishes include 28 species grouped into four genera:Family Adrianichthyidae
- Genus Adrianichthys
- Adrianichthys kruyti - Duckbilled buntingi
- Adrianichthys roseni
- Genus Horaichthys
- Horaichthys setnai - Malabar ricefish
- Genus OryziasOryziasOryzias is a genus of fish in the Adrianichthyidae family.It contains the following species:* Oryzias latipes * Oryzias bonneorum Parenti, 2008* Oryzias carnaticus...
- Oryzias carnaticus
- Oryzias celebensisOryzias celebensisOryzias celebensis is a species of fish in the Adrianichthyidae family. It is endemic to Indonesia.-Source:* World Conservation Monitoring Centre 1996. . Downloaded on 4 August 2007....
- Celebes medaka - Oryzias curvinotus - Hynann ricefish
- Oryzias dancena
- Oryzias haugiangensis
- Oryzias hubbsi
- Oryzias javanicus - Javanese ricefish
- Oryzias latipesOryzias latipesOryzias latipes, also known as Medaka and Japanese killifish, is a member of genus Oryzias , the only genus in the subfamily Oryziinae. This rather small...
- Japanese rice fish - Oryzias luzonensis
- Oryzias marmoratusOryzias marmoratusOryzias marmoratus is a species of fish in the Adrianichthyidae family. It is endemic to Indonesia.-Source:* Kottelat, M. 1996. . Downloaded on 4 August 2007....
- Marmorated medaka - Oryzias matanensisOryzias matanensisOryzias matanensis is a species of fish in the Adrianichthyidae family. It is endemic to Indonesia.-Source:* Kottelat, M. 1996. . Downloaded on 4 August 2007....
- Matano medaka - Oryzias mekongensis
- Oryzias melastigma
- Oryzias minutillus - Dwarf medaka
- Oryzias nebulosus
- Oryzias nigrimas - Black buntingi
- Oryzias orthognathus - Sharpjawed buntingi
- Oryzias pectoralis
- Oryzias profundicolaOryzias profundicolaOryzias profundicola is a species of fish in the Adrianichthyidae family. It is endemic to Indonesia.-Source:* Kottelat, M. 1996. . Downloaded on 4 August 2007....
- Yellow finned medaka - Oryzias sinensis
- Oryzias songkhramensis
- Oryzias timorensis
- Oryzias uwai
- Genus XenopoecilusXenopoecilusXenopoecilus is a genus of fish in the Adrianichthyidae family. It can only be found in Lake Poso, Indonesia, and is a critically endangered species...
- Xenopoecilus oophorus - Eggcarrying buntingi
- Xenopoecilus poptae - Popta's buntingi
- Xenopoecilus sarasinorumXenopoecilus sarasinorumXenopoecilus sarasinorum is a species of fish in the Adrianichthyidae family. It is endemic to Indonesia.-References:* Kottelat, M. 1996. . Downloaded on 5 August 2007....
- Sarasins minnow