Nannostomus is a genus of fish belonging to the characin family Lebiasinidae. All of the species in this genus are known as pencil fish, a popular name that was initially only applied to two species in the 1920s, Nannostomus unifasciatus and Nannostomus eques, by the late 1950s however, the term would be applied to all members of the genus. Several species have become popular aquarium fish due to their attractive coloration, unique shape, and interesting demeanor.
The flavescent peacock, also known as Grant's peacock, is a species of haplochromine cichlid. Its common name refers to its "flavescent" (yellowish) colour.
Nannostomus harrisoni,, is a species of pencil fish. Native to The Guianas, the species displays a single horizontal stripe of intense black, and blood red adornments on its fins. N. harrisoni is often confused with Nannostomus unifasciatus, another long, slender, single-striped species with similar profile and coloration, but N. harrisoni swims in a horizontal posture, as opposed to the snout-up oblique posture of N.unifasciatus, and the bright red adornments on the ventral fins of N. harrisoni are absent in N. unifasciatus. Though the recently described species N. grandis has been dubbed the largest member of the genus, adults of N. harrisoni commonly grow to a length of 70 mm, making it in fact the largest species of pencil fish described to date. It is commonly known as Harrison's pencilfish.
The butterfly barb is a species of cyprinid fish in the genus Enteromius.
Oxynoemacheilus bergianus, the Kura sportive loach, is a species of ray-finned fish in the genus Oxynoemacheilus. This species is found in Lake Urumiyeh and Namak Lake basins in Iran, in the southern Caspian basin from Kura east to the Sefid-Rud drainage. It can also be found in the headwaters of Tigris in Turkey, Iraq and in Karoun, Iran as well as those of the Euphrates in Turkey and possibly in Syria and Iraq. It lives in fast flowing streams and rivers with gravel and rocky substrates and does not tolerate impoundments, dam construction having been identified as a major potential threat to this species.
Derhamia hoffmannorum is a species of freshwater fish endemic to Guyana, where it is found in the Mazaruni River. It is the only species in the genus Derhamia. It is found in fresh water at pelagic depths in a tropical climate. The average length of an unsexed male is about 6.1 cm (2.4 in). It has an elongated body with large eyes. It is a timid species compared to other similar species such as the various pencilfish. They live near the surface of water and are known to hide whenever possible, usually under floating objects. This species only eats what can be found at the surface, as well. D. hoffmannorum will not seek food that sinks to the bottom.
Nannostomus anduzei is a freshwater species of fish belonging to the genus Nannostomus in the characin family Lebiasinidae. It is native to Venezuela and northern Brazil, particularly the upper Orinoco and Rio Ererê, a tributary of the Rio Negro. The adults grow to a maximum length of only 16 mm, making them one of the smallest pencilfish. Other common names include miniature pencilfish, miniature nannostomus, and Anduzi's nannostomus.
Nannostomus beckfordi,, commonly known as the golden pencil fish or Beckford's pencil fish, is a freshwater species of fish belonging to the characin family Lebiasinidae. It occurs widely and commonly in swamps and slow-moving waters in Brazil, Guyana, French Guiana, and Suriname.
Nannostomus bifasciatus,, is a freshwater species of fish belonging to the characin family Lebiasinidae. It is commonly known as the two-lined pencilfish. It can be found in slow-moving swamps and rivers in French Guiana and Suriname.
Nannostomus britskii,, commonly known as the spotstripe pencilfish, is a freshwater species of fish belonging to the family Lebiasinidae of characins. They were first described in 1978 by Stanley H. Weitzman along with two other new species, from a collection of specimens preserved in the São Paulo museum. They have been recorded from only two localities, both in Brazil. No live specimens had been seen, collected, or exported for the aquarium trade until very recently.
Nannostomus digrammus,, commonly known as the twostripe pencilfish, is a freshwater species of fish belonging to the characin family Lebiasinidae. They were first described in 1913 by Henry Weed Fowler and are fairly typical of members of this genus being small, elongated fish with prominent horizontal stripes, in this case limited to two dominant stripes, usually maroon in color. They are recorded as native to Brazil and Guyana, where they occur fairly widely, but are seen only occasionally in the aquarium trade.
Nannostomus eques,, commonly known as the diptail,brown or hockey stick pencilfish, is a freshwater species of fish belonging to the characin family Lebiasinidae. It was first described in 1876 by Franz Steindachner making it one of the first members of the genus to be discovered and described. It is fairly typical of members of this genus being a small, elongated fish with prominent horizontal stripes. It occurs quite widely in South America, having been recorded in Brazil, Peru, Colombia, and Guyana. It is also quite commonly met with in the aquarium trade where its habit of swimming and posturing at a 'snout-up' angle—one of two Nannostomus species to do so, the other being Nannostomus unifasciatus—makes it a popular choice.
Nannostomus limatus,, commonly known as the elegant pencilfish, is a freshwater species of fish belonging to the characin family Lebiasinidae. They were first described in 1978 by Stanley H. Weitzman along with two other new species, from a collection of specimens preserved in the São Paulo museum. Only rarely imported and kept by aquarists, they have been recorded from the Amazonian region of Brazil, specifically near Santarém.
Nannostomus minimus,, commonly known as the least pencilfish, is a freshwater species of fish belonging to the characin family Lebiasinidae. It is restricted to Guyana, where it has been reported from the Potaro and Mazaruni Rivers.
Nannostomus mortenthaleri, commonly known as the coral red pencilfish, is a freshwater species of fish belonging to the characin family Lebiasinidae. It is one of the most colourful of the genus, being suffused with a bright coral red colouration over its entire body and fins, in striking contrast to its horizontal jet black stripes. It was originally described as a subspecies of Nannostomus marginatus, but it is now recognised as a species in its own right. Mature males have a thickened anal fin. Maximum length is 29mm.
The fourspine leaffish, is a species of in the Nandidae native to rivers and streams in Ivory Coast and Ghana. Although placed in the family Nandidae by FishBase, most recent authorities place Afronandus in Polycentridae. The specific name honours the collector of the type, Leo Sheljuzhko (1890–1969), a Ukrainian-German entomologist who sent the type to Meinken.
Copeina osgoodi is a species of fish in the Copeina genus found in the upper Amazon basin. They grow up to 5.1 centimetres (2.0 in).
Pyrrhulina marilynae is a species of fish in the Pyrrhulina genus found in the basins of the Tapajós and Xingu River. They grow no more than a few centimeters.
The Burmese mullet is a species of freshwater ray-finned fish, a mullet belonging to the family Mugilidae. It is the only species in the genus Sicamugil. It is found in the drainage systems of the Sittang and Irrawaddy rivers in Myanmar.
Alestopetersius brichardi is a species of African tetra. It is found in the Malebo Pool, the middle Congo River, the Ruki River drainage and the Lomami River in the Democratic Republic of the Congo.
