The Hemidontidae is a small family

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...

 of freshwater characin

Characidae

The Characidae, characids or characins are a family of freshwater subtropical and tropical fish, belonging to the order Characiformes. The name "characins" is the historical one, but scientists today tend to prefer "characids" to reflect their status as a by and large monophyletic group at family...

s found in northern South America, south to the Paraná

Paraná River

The Paraná River is a river in south Central South America, running through Brazil, Paraguay and Argentina for some . It is second in length only to the Amazon River among South American rivers. The name Paraná is an abbreviation of the phrase "para rehe onáva", which comes from the Tupi language...

-Paraguay

Paraguay

Paraguay , officially the Republic of Paraguay , is a landlocked country in South America. It is bordered by Argentina to the south and southwest, Brazil to the east and northeast, and Bolivia to the northwest. Paraguay lies on both banks of the Paraguay River, which runs through the center of the...

 Basin. The larger species are popular food fish.

Hemiodontids have a streamlined body shape; many are fast-swimming, and are able to leap out of the water to escape predators. In the adults of all species except Micromischodus sugillatus, there are no teeth on the lower jaws. Most species have a round spot on the side of the mid-body and a stripe along the lower lobe of the caudal fin. The largest hemiodontids are around 50 centimetres (19.7 in) in length.

Species

The family has five genera

Genus

In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 and around 29 known species

Species

In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

, as well as several undescribed species.

Family Hemiodontidae

• Subfamily Anodontinae
  • Genus Anodus
    • Anodus elongatus
    • Anodus orinocensis
  • Genus Micromischodus
    • Micromischodus sugillatus
• Subfamily Hemiodontinae
  • Tribe Hemiodontini
    • Genus Hemiodus
      • Hemiodus amazonum
      • Hemiodus argenteus
      • Hemiodus atranalis
      • Hemiodus goeldii
      • Hemiodus gracilis
      • Hemiodus huraulti
      • Hemiodus immaculatus
      • Hemiodus jatuarana
      • Hemiodus microlepis
      • Hemiodus orthonops
      • Hemiodus parnaguae
      • Hemiodus quadrimaculatus - Barred hemiodus
      • Hemiodus semitaeniatus - Halfline hemiodus
      • Hemiodus sterni
      • Hemiodus ternetzi
      • Hemiodus thayeria
      • Hemiodus tocantinensis
      • Hemiodus unimaculatus
      • Hemiodus vorderwinkleri
  • Tribe Bivibranchiini
    • Genus Argonectes
      • Argonectes longiceps
      • Argonectes robertsi
    • Genus Bivibranchia
      • Bivibranchia bimaculata
      • Bivibranchia fowleri
      • Bivibranchia notata
      • Bivibranchia simulata
      • Bivibranchia velox