Bryconops gracilis | |
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Live (top) and preserved (bottom) specimens | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Actinopterygii |
Order: | Characiformes |
Family: | Iguanodectidae |
Genus: | Bryconops |
Species: | B. gracilis |
Binomial name | |
Bryconops gracilis Eigenmann, 1908 | |
Bryconops gracilis is a small species of freshwater fish from the rivers of South America. It is one of multiple species for which the common name "lambari" is used. Though not well-studied, it has been re-described in recent years in order to differentiate it from Bryconops alburnoides, a congener to which it bears a strong resemblance.
The holotype of Bryconops gracilis - the very first collected specimen - was reported at 7.5 cm (2.9 in) in SL (standard length, with the length of the tail fin excluded). [2] Further specimens of B. gracilis range from 6.1 to 12.3 cm (2.4 to 4.8 in) SL. [3] Like the rest of Bryconops, B. gracilis has a slender body reminiscent of a minnow's. [4] Its body is also on the shallower side when compared to other members of its genus, a feature it shares with B. alburnoides , B. collettei , and B. magoi . [5]
Bryconops gracilis is frequently confused with congener Bryconops alburnoides , the type species of the genus. This is because they share several morphological traits, such as a yellowish caudal fin, high number of lateral line scales, and overall elongated body shape. [3] Both B. gracilis and B. alburnoides have 54 to 62 pored lateral line scales. [5] Early descriptions also drew comparisons to Bryconops melanurus (then called Creatochanes melanurus) due to morphological overlap. [6]
When it was originally described by German-American ichthyologist Carl H. Eigenmann in 1908, B. gracilis was named Creatochanes gracilis. [2] It is still occasionally referenced under that name. [7]
Eigenmann's original nomenclature retains an element of validity in the current day. This is because there are two subgenera in Bryconops, Bryconops and Creatochanes, and the latter draws from Eigenmann's work. However, B. gracilis belongs to the subgenus Bryconops, making its full name Bryconops (Bryconops) gracilis. [5] It shares this subgenus with congener B. alburnoides, with which it has been confused in the past, but similar congener B. melanurus is in Creatochanes. [8]
Bryconops gracilis is an iguanodectid (part of the family Iguanodectidae). [9] This is a fairly recent classification, and was prompted by a review of the family Characidae in 2011 wherein the genera Bryconops , Piabucus , and Iguanodectes were all moved from Characidae to Iguanodectidae. [10] Some sources still list B. gracilis as a characin. [11]
The specific epithet gracilis means "slender" (note the similarity to the word "graceful"), and is in reference to the narrow, elongated body. [12] It shares this specific epithet with multiple other species, such as Hemiodus gracilis and Pseudanos gracilis. [13]
In terms of a common name, B. gracilis is sometimes called the "lambari", [1] but this is a name that also applies to other small species of fish in nearby regions. These fish include Astyanax altiparanae, [14] Bryconamericus lambari, [15] and Deuterodon iguape. [16] Otherwise, B. gracilis has no accepted common name. [17]
Bryconops gracilis is native to Brazil, found only in the Tapajos river basin. [18] Three of its congeners have also been described therein: B. durbinae , B. munduruku , and B. transitoria . [8]
Though B. gracilis is currently listed as least concern by the International Union for the Conservation of Nature (IUCN), [1] the Tapajos river is under constant threat of human impact. The water is sometimes so full of sediments kicked up by illegal mining that entire portions of the river turn entirely brown.[ citation needed ] Factors like this place B. gracilis, as well as other species endemic to the area, under greater survival pressure. [19]
Bryconops is a genus of freshwater fish in the family Iguanodectidae from South America. It consists of small fish, all under half-a-foot long, with slender bodies and silvery scales, though there is some mild color variation. Several species can be identified by way of a humeral patch, and others have a reddish ocellus, or eyespot, on one or both lobes of the dorsal fin.
Iguanodectidae is a family of freshwater fish in the order Characiformes that lives in South America. It is home to the subfamily Iguanodectinae and the monotypic Bryconops clade. Several species in the family, such as the green line lizard tetra, the tailspot tetra, and the orangefin tetra, are sometimes taken as aquarium fish.
The orangefin tetra is a small species of freshwater fish from South America that belongs to the family Iguanodectidae. Though common in its native range, it seems to prefer fast-flowing and shallow creeks. It is an active swimmer that feeds on plant material and various invertebrates, sometimes jumping out of the water to catch prey above the surface.
Bryconops alburnoides is a small freshwater fish, approximately 6 inches long at its largest, that lives in the rivers of South America. It has a slender body, with a yellowish dorsal fin and yellow-tinged back scales that fade into silver on its belly. It is largely an insectivore that picks land-dwelling insects from the riverbanks, though it eats much more whenever rain washes prey into the water.
The tailspot tetra is a freshwater fish that lives in the coastal river regions of upper South America. Both its common and scientific names reference the distinct spot of color present on the tail fin, which is one of its defining characteristics. It is a small fish, reaching 4.8 in at its longest. Despite its small size, it is an active swimmer, with a preference for fast-flowing waters.
Bryconops cyrtogaster is a midsize species of freshwater fish found in the Oyapock river in French Guiana and Brazil. It is overall silver, with an indistinct dark patch at the base of the tail fin that spreads onto the fin rays slightly. Originally described in 1926 under a different baisonym, it was the subject of a redescription in June 2020.
Bryconops durbinae, sometimes listed under the name Bryconops durbini, is a small species of freshwater fish in the family Iguanodectidae. It is the smallest species of the genus Bryconops, and is endemic to the Tapajós river basin in Brazil.
Bryconops giacopinii is a mid-sized species of freshwater fish in the family Iguanodectidae. It is the largest member of the genus Bryconops, and is therefore difficult to confuse with any of its congeners. With a diet that consists largely of land-dwelling insects, it serves as an important link between the terrestrial and aquatic aspects of its native range.
Bryconops humeralis is a small freshwater fish distributed across northern South America. The name "humeralis" means "relating to the shoulder", in reference to the distinct humeral patches that the fish sports. It is slightly longer than average in terms of the genus Bryconops, though still firmly within the standard range, and is slightly more slender than is usual for its congeners.
Bryconops inpai is a small freshwater fish native to the rivers of South America. It only lives in two particular river systems - the Casiquiare and Negro - which means that its range is restricted to the northern half of the continent. It has indistinct humeral spots, and is bluish-silver in life, which is unusual for members of Bryconops; they are more often plain silver or greenish-silver.
Bryconops melanurus, sometimes called the tail-light tetra, is a small species of freshwater fish from South America that primarily preys on insects. It lives in small schools and is an active swimmer, which means that it requires open space in its habitat. Nonetheless, it does not demonstrate a strong preference for any one biotope within its native range.
Bryconops munduruku is a small freshwater fish of the family Iguanodectidae that lives in the rivers of South America. Its adipose fin is black, with a clear base, and it has two humeral spots, which is a feature it shares with few congeners. Its fins are a variety of yellow, red, black, and clear, and mature males have hooks on select fin-rays.
Bryconops piracolina is a small fish that inhabits the waters of Brazil. It is slender and silvery in color, like many fish in Bryconops, but can be distinguished from other members by way of its dorsal fin, which has a black patch of color extending up from the fin-base; congeners usually have light pigment in the dorsal fin, or a brighter color.
Bryconops transitoria is a small freshwater fish that lives in the rivers of South America. It is a poorly-studied member of the genus Bryconops with few records and vague distribution accounts, though it is believed to be endemic to the Rio Tapajós. It was originally thought to be a subspecies of congener Bryconops melanurus, but is now accepted as its own species.
Bryconops vibex is a small freshwater fish from the rivers of Venezuela, known solely from the Rio Cataniapo. The body is slender, though with an element of sturdiness, and it has one humeral spot by each pectoral fin. It bears visual similarities to several congeners, but can be differentiated by way of many factors.
Bryconops allisoni is a species of freshwater fish known from the rivers of Brazil. It is a recent addition to the genus (2019), currently considered a member incertae sedis. Its name honors Antonio Machado-Allison, an ichthyologist responsible for a great deal of work on the genus Bryconops.
Bryconops chernoffi is a species of freshwater fish that inhabits the rivers of Brazil. Specifically, it is found in the Rio Maicuru and Rio Ipixuna; the latter is a tributary of the former, which is a tributary of the Amazon river main. B. chernoffi demonstrates a preference for clear-water streams with sandy and rocky bottoms.
Bryconops florenceae is a small freshwater fish that inhabits the rivers of South America. Comprehensive research is lacking due to B. florenceae being the most recently described of the genus, but researchers believe it to be a relatively widespread species. It is found throughout the Maroni, Mana, and Sinnamary river basins, which defines its range within Suriname and French Guiana.
Bryconops hexalepis is a small iguanodectid fish from the rivers of Brazil. It is solely found in the drainage of the Rio Tocantins. Rather elongate and quite slender, it is considered one of the smaller species of its genus, with tall scales and large eyes.
Bryconops marabaixo is a small freshwater fish from the lower Amazon basin, native to the Rio Jari. It is small and silvery, with a dark-gray back, and its fins are mostly clear, though the caudal fin has a dark stripe on the lower margin of the dorsal lobe, and a spot of red pigment just above that. Like many other members of Bryconops, it has a humeral spot, which is a mark near each pectoral fin.