Arapaimidae | |
---|---|
Arapaima sp. | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Actinopterygii |
Order: | Osteoglossiformes |
Family: | Arapaimidae Bonaparte, 1846 |
Genera [1] | |
Synonyms | |
Sudidinae |
Arapaimidae is a family of freshwater ray-finned fish belonging to the family Osteoglossidae. It includes the South American arapaimas of the Amazon and Essequibo basins and the African arowana (Heterotis niloticus) from the watersheds of the Sahelo-Sudanese region, Senegal, Gambia, and parts of Eastern Africa. [1] This family is sometimes treated as the subfamily Arapaiminae. [2] [3] A commonly used synonym is Heterotidinae, [4] but according to the ICZN, Arapaimidae has priority. [2]
Arapaimides, along with other osteoglossomorphs, are of phylogenetic and evolutionary interest due to their trans-oceanic distribution, excellent fossil record, and position as one of the oldest living teleost lineages. [3] The type-species of the group, Arapaima gigas , is an important South American food source and charismatic representative of the region. [5] Both Arapaima and Heterotis are cultured for food in their respective countries due to their heartiness and meat, and the arapaima is a prized sport-fish, being the largest truly freshwater fish. [6]
The internal placement of Osteoglossomorpha within crown-group teleosts is contested, with competing morphological and molecular analyses placing them either as sister to all other extant teleosts, or internal to Elopimorpha and sister to the clade consisting of Otocephala and Euteleostei. [2] [7]
The placement and name of the clade containing Arapaima and Heterotis is also uncertain. Some include this clade in the family Osteoglossidae with the South American and Asian arowana. [6] Others place Arapaima and Heterotis together in their own family, Arapaimidae.
Arapaima taxonomy was recently revised to revalidate old names and describe a new species, proposing 6 existing species (see below) and invalidating current museum specimens. [5] [8] [9] However, these four proposed or reestablished species are known only from singular holotype specimens, and only that of A. mapae and A. leptostoma still currently exist. [5] [8] [9] Typically, all species of Arapaima described by Valenciennes, Spix, and Agassiz are referred to as A. gigas, though current taxonomy could be revised with more thorough evidence. [8] Currently, population genetic evidence supports a singular Arapaima species with two distinct genetic populations: an Amazonas population (exhibiting a pattern of isolation by distance), and an Araguaia-Tocantins basin population. [8] There is little debate that Heterotis is a monotypic genus represented by only H. niloticus.
Arapaimides are characterized by elongate, slender bodies with large scales and long dorsal and anal fins positioned close to a short caudal peduncle. [1] [3] The pelvic fins are small and abdominal if present. [1] [3] They lack chin barbels, have a glossolaryngeal (tongue) bone with teeth present, and the premaxillae are fixed to the skull. [1] [3] Branched caudal fin rays are less than sixteen, branchiostegal rays between three and seven, and hypurals less than 6. [1] [3] Heterotis possesses a specialized suprabranchial organ for concentrating and filtering small food particles. [1] [7]
Both genera make use of similar freshwater habitats in the respective region, with Arapaima found in the floodplains of the Amazon and Esequibo river basins of South America and Heterotis found in littoral zones of large, open rivers in all Sahelo-Sudanese basins of Africa. [10] [11] Arapaima is typically a top-water fish predator, while Heterotis is a benthic mud-filterer primarily feeding on phytoplankton and small crustaceans with their suprabranchial organ. [10] [11] Both groups are obligate air-breathers and nest-builders, with males guarding eggs and young. [10] [11]
A genetic study shows that Arapaimidae diverged from Osteoglossinae about 220 million years ago, during the Late Triassic. Within Osteoglossinae, the lineage leading to the South American Osteoglossum arowanas diverged about 170 million years ago, during the Middle Jurassic. The Asian and Australian arowanas in the genus Scleropages separated about 140 million years ago, during the Early Cretaceous. [12] [13]
Originally, it was thought that the breakup of Gondwana 150 – 30 million years ago was the evolutionary cause of the trans-continental distribution of the osteoglossomorphs. However, minimum ages of intercontinental clades and presence of marine forms in the fossil records imply that ancestral trans-oceanic dispersal is possible. Tests of these hypotheses are currently inconclusive as they are dependent on an a priori calibrated age of crown-group Teleostei, about which fossil and molecular evidence disagree. I.e., hypotheses do not fail only if Teleostei are of Permian origin, but molecular inferences push crown ages further back. [3] [12] [13] [9]
Both Arapaima and Heterotis are farmed in their respective regions as relatively large and hardy food-fish. [1]
The family is named after the monotypic genus Arapaima, whose name derives from the Tupi-Guyarana indigenous name for Arapaima gigas.
Osteoglossiformes is a relatively primitive order of ray-finned fish that contains two sub-orders, the Osteoglossoidei and the Notopteroidei. All of at least 245 living species inhabit freshwater. They are found in South America, Africa, Australia and southern Asia, having first evolved in Gondwana before that continent broke up. In 2008, several new species of marine osteoglossiforms were described from the Danish Eocene Fur Formation, dramatically increasing the diversity of this group. This implies that the Osteoglossomorpha is not a primary freshwater fish group with the osteoglossiforms having a typical Gondwana distribution.
Arowanas are freshwater bony fish of the subfamily Osteoglossinae, also known as bony tongues. In this family of fish, the head is bony and the elongated body is covered by large, heavy scales, with a mosaic pattern of canals. The dorsal and anal fins have soft rays and are long based, while the pectoral and ventral fins are small. The name "bonytongues" is derived from a toothed bone on the floor of the mouth, the "tongue", equipped with teeth that bite against teeth on the roof of the mouth. The arowana is a facultative air breather and can obtain oxygen from air by sucking it into its swim bladder, which is lined with capillaries like lung tissue.
Osteoglossomorpha is a group of bony fish in the Teleostei.
The Asian arowana comprises several phenotypic varieties of freshwater fish distributed geographically across Southeast Asia. While most consider the different varieties to belong to a single species, work by Pouyaud et al. (2003) differentiates these varieties into multiple species. They have several other common names, including Asian bonytongue, dragonfish, and a number of names specific to the different color varieties.
The arapaima, pirarucu, or paiche is any large species of bonytongue in the genus Arapaima native to the Amazon and Essequibo basins of South America. Arapaima is the type genus of the subfamily Arapaiminae within the family Osteoglossidae. They are among the world's largest freshwater fish, reaching as much as 3 m (9.8 ft) in length. They are an important food fish. They have declined in the native range due to overfishing and habitat loss. In contrast, arapaima have been introduced to several tropical regions outside the native range, where they are sometimes considered invasive species. In Kerala, India, arapaima escaped from aquaculture ponds after floods in 2018. Its Portuguese name, pirarucu, derives from the Tupi language words pira and urucum, meaning "red fish".
Osteoglossidae is a family of large-sized freshwater fish, which includes the arowanas. They are commonly known as bonytongues. The family has been regarded as containing two extant subfamilies Arapaiminae and Osteoglossinae, with a total of five living genera, but these are regarded as valid families in Eschmeyer's Catalog of Fishes The extinct Phareodontinae are known from worldwide during the Late Cretaceous and Paleogene; they are generally considered to be crown group osteoglossids that are more closely related to one of the extant osteoglossid subfamilies than the other, though their exact position varies.
Arapaima gigas, also known simply as Arapaima or pirarucu, is a species of arapaima native to the basin of the Amazon River. Once believed to be the sole species in the genus, it is among the largest freshwater fish. The species is an obligate air breather, so it needs to come to the surface regularly to breathe air.
The Asiatic glassfishes are a family, the Ambassidae, of freshwater and marine ray-finned fishes that were formerly classified in the order Perciformes, but most authorities consider this order to be paraphyletic and that the Ambassidae are of uncertain affinities, incertae sedis, but within the subseries Ovalentaria. The species in the family are native to Asia, Oceania, the Indian Ocean, and the western Pacific Ocean. The family includes eight genera and about 51 species. Some species are known as perchlets.
The African arowana or Nile arowana is a species of bonytongue. Despite being called an "arowana", the African arowana is more closely related to arapaimas, the only other members in the subfamily Arapaiminae, than the South American, Asian, and Australian arowanas in the subfamily Osteoglossinae. Compared to these, the African arowana has a more terminal mouth and is the only one that feeds extensively on plankton.
Scleropages is a genus of fish in the family Osteoglossidae found in Asia and Australia. All of these species are carnivorous and have great jumping ability. These species are highly valued as aquarium fish, particularly by those from Asian cultures. In 2003, a study redescribed several naturally occurring color varieties of S. formosus into four separate species. The majority of researchers dispute these redescriptions, arguing that the published data are insufficient to justify recognizing more than one Southeast Asian species of Scleropages and that divergent haplotypes used to distinguish the color strains into isolated species were found within a single color strain, contradicting the findings. They are considered monotypic, consisting of closely related haplotypes based on color. The ancestor of the Australian arowanas: S. jardinii and S. leichardti, diverged from the ancestor of the Asian arowanas about 140 million years ago, during the Early Cretaceous period. The morphological similarity of all seven species shows that little evolutionary change has taken place recently for these ancient fish. The genus had a much wider distribution during the early Cenozoic, with fossil remains known from the Paleocene of Niger and Belgium, and from the Eocene of China.
The black arowana is a South American freshwater bony fish of the family Osteoglossidae. Black arowanas are sometimes kept in aquariums, but they are predatory and require a very large tank. It is generally common, but large numbers are caught as food and for the aquarium fish trade.
The freshwater butterflyfish or African butterflyfish is a species of osteoglossiform fish native to freshwater habitats in the Niger and Congo basins of western and central Africa. It is the only extant species in the family Pantodontidae. It is not closely related to saltwater butterflyfishes.
The Serrasalmidae (serrasalmids) are a family of characiform fishes, recently elevated to family status. It includes more than 90 species. The name means "serrated salmon family", which refers to the serrated keel running along the belly of these fish. Fish classified as Serrasalmidae are also known by these common names: pacu, piranha, and silver dollar. These common names generally designate differing dental characteristics and feeding habits.
Lycoptera is an extinct genus of fish that lived from Lower Cretaceous, Barremian to Aptian in present-day China, North Korea, Mongolia and Siberia. Although there is record from Jurassic Formation in Siberia, its age remains questionable. It is known from abundant fossils representing sixteen species, which serve as important index fossil used to date geologic formations in China. Along with the genus Peipiaosteus, Lycoptera has been considered a defining member of the Jehol Biota, a prehistoric ecosystem famous for its feathered dinosaurs, which flourished for 20 million years during the Early Cretaceous, where it occurs abundantly in often monospecific beds, where they are thought to have died in seasonal mass death events. Lycoptera is a crown group teleost belonging to an early diverging lineage of the Osteoglossomorpha, which contains living mooneyes, arapaima, arowana, elephantfish and knifefish/featherbacks.
Opsithrissops is an extinct genus of prehistoric bony fish that lived during the Thanetian stage of the Paleocene epoch. It is a 120 centimetres (3.9 ft) fish in the family Osteoglossiformes which includes other bony-tongues such as the extant species of arowana and arapaima.
Brychaetus is an extinct genus of prehistoric marine bonytongue fish known from the Late Cretaceous to the late Eocene of Europe, North America, and northern Africa.
Petrocephalus is a genus of ray-finned fish in the family Mormyridae. All the fish species of this genus are endemic to Africa.
Arapaima leptosoma is a species of freshwater fish endemic to Brazil. It is a member of the arapaimas, a genus of air-breathing fish that contains some of the world's largest freshwater fish. Like other members of the genus Arapaima, this fish can breathe air. It is known only from the confluence of the Solimões and Purus Rivers in Amazonas, Brazil, although due to the lack of obvious geographic barriers, it likely has a larger range.
Percomorpha is a large clade of ray-finned fish with more than 17 000 known species that includes the tuna, seahorses, gobies, cichlids, flatfish, wrasse, perches, anglerfish, and pufferfish.
The Anabantiformes, is an order of bony fish (Teleostei) proposed in 2009. They are collectively known as labyrinth fish, are an order of air-breathing freshwater ray-finned fish with two suborders, five families and at least 207 species. In addition, some authorities expand the order to include the suborder Nandoidei, which includes three families - the Nandidae, Badidae and Pristolepididae - that appear to be closely related to the Anabantiformes. The order, and these three related families, are part of a monophyletic clade which is a sister clade to the Ovalentaria, the other orders in the clade being Synbranchiformes, Carangiformes, Istiophoriformes and Pleuronectiformes. This clade is sometimes referred to as the Carangaria but is left unnamed and unranked in Fishes of the World. This group of fish are found in Asia and Africa, with some species introduced in United States of America.