Astyanax atratoensis

Last updated

Contents

Astyanax atratoensis
FMIB 52393 Astvanax atratornsis.jpeg
1907 illustration
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Characiformes
Family: Characidae
Genus: Astyanax
Species:
A. atratoensis
Binomial name
Astyanax atratoensis
Eigenmann, 1907

Astyanax atratoensis is a small freshwater fish that occupies the Atrato river basin in Colombia. Originally described from a tributary therein, the Truandó River, it gets its specific epithet from the region. Though it faces no imminent threats, A. atratoensis inhabits waterways with a history of severe environmental pressure in the form of anthropogenic pollution. Several restoration efforts have been undertaken in the relevant regions.

Populations exist at both low and high elevations, and have adapted to their respective surroundings; higher-elevation specimens have deeper bodies than lower-elevation ones. The color pattern, however, remains the same - largely silver, with a reflective silver lateral stripe and a small blotch of pigment on the caudal peduncle. It also has an ovoid humeral spot with vertical elongation, which can be used to differentiate it from similar congeners.

Taxonomy

Astyanax atratoensis was first described by prolific German-American ichthyologist Carl H. Eigenmann in 1907, with findings published in the relevant edition of the Proceedings of the United States National Museum. [2] The article was co-authored by Fletcher Ogle, a fellow ichthyologist. [3] The type specimen has since gone missing, though when this happened is unknown. [4]

In the nominal article, Eigenmann remarked that A. atratoensis is closely related to congener Astyanax caucanus , which was named by Austrian ichthyologist Franz Steindachner in 1879. [5] Further, it is related to multiple other species of Astyanax that all share the subgenus Zygogaster, to which A. atratoensis was originally designated. [6] More modern interpretations often place it in the subgenus Poecilurichthys. [7] [8]

Etymology

Given that A. atratoensis is endemic to the Atrato River basin in Colombia, its specific epithet originates therein. The genus name "Astyanax" is slightly less clear, as it had no defined reasoning in the original text, but the allusion lies in Homer's Iliad; Astyanax was a warrior of Troy, and the son of prince Hector. [9] One possible reason for such a name is that the scales of type species Astyanax argentatus are large and silvery, such that they could be compared to armor or a shield. [10]

Description

Astyanax atratoensis is subrhomboidal in body shape, and commonly reaches a maximum length of roughly 10.3 cm (4.1 in) standard length (SL). [9] It is possible for the fish to reach nearly twice that length, however; specimens from a particular delta in the Arato River were as large as 21.5 cm (8.5 in) total length. [11] It is largely an iridescent silver, with a distinct humeral spot of a vertically elongated oval shape. There is a silver lateral stripe that terminates at a small dark blotch on the caudal peduncle. [5]

There are between 35 and 39 rays in the anal fin (depending on the source consulted), which can be used as an identifying characteristic when comparing A. atratoensis to similar congeners. [5] [12] The dorsal fin has 10–11 rays, [5] and the predorsal series of scales is incomplete. [8] Though environment can affect morphology, resulting in a deeper body at higher elevations, separate populations of A. atratoensis do not demonstrate differences severe enough to warrant confusion with another species. [6] [13]

Distribution and ecology

Astyanax atratoensis is endemic to its namesake, the Atrato River basin in Colombia. Its type locality is the Truandó River. [1] It can be found at both high and low elevations within the basin, and the environment in which a particular specimen was found can have an impact on its morphology. Specifically, populations of A. atratoensis at higher elevations have a deeper body than those at lower elevations, which are more fusiform. The reasons for this differentiation are unclear, but current hypotheses include differing riparian zones, hydrological features like current speed, and risk of exposure to predatory birds. [13]

Other members of the genus in regions with healthy riparian vegetation tend to be adaptable omnivores that consume plentiful allochthonous material. [14] [15] When it comes to the dietary needs and preferences of A. atratoensis in particular, details are sparse.

Conservation status

Astyanax atratoensis is considered a species of least concern by the IUCN. Despite a somewhat restricted distribution, nothing currently serves as an imminent threat to population levels, and so A. atratoensis is not endangered. [1]

Its native range, however, may face some environmental pressure. The Atrato River basin has a history of severe pollution. Nonetheless, recent action - most notably a court ruling in 2016 - has prompted conservation and cleanup efforts, largely on the part of the Colombian government. [16] The 2016 ruling sought out a different approach to conservation in that, rather than enacting protective legislation, the Colombian Constitutional Court recognized the river as its own distinct entity deserving of protection and restoration, as a human would be; as of 2021, this had resulted in only minor project implementation, with several larger aspects still in the planning stages. [17]

Related Research Articles

<i>Astyanax</i> (fish) Genus of fishes

Astyanax is a genus of freshwater fish in the family Characidae of the order Characiformes. Some of these fish, like many of their relatives, are kept as aquarium pets and known collectively as tetras. With around 150 described species and new ones being described yearly, this genus is among the largest of the entire order; Hyphessobrycon also has more than 145 species and which one is larger at any one time depends on whether more species have been recently described in one or the other. The blind and colorless cave tetra of Mexico is a famous member of the genus, but its taxonomic position is disputed: Some recognize it as part of the Mexican tetra and this is supported by phylogenetic evidence, but others recognize the cave form as a separate species, A. jordani.

<i>Carlastyanax</i> Genus of fishes

Carlastyanax aurocaudatus is a small species of freshwater fish in the family Characidae native to the Río Cauca in Colombia. It is the only member of the monotypic genus Carlastyanax, which was named in 1972 specifically for the species by Jacques Géry. Upon description, it was named Astyanax aurocaudatus by Carl H. Eigenmann. There has been debate concerning whether or not the genus should be recognized, but C. aurocaudatus is currently considered a valid species.

<i>Astyanax argentatus</i> Species of fish

Astyanax argentatus is a small freshwater fish native to northern Central America and southern North America. Given its native range, it is also known as the Texan tetra. Little has been published regarding the feeding habits or behavior of A. argentatus, but it is known to have the northernmost distribution of any member of the genus Astyanax.

<i>Astyanax acatlanensis</i> Species of fish

Astyanax acatlanensis, sometimes called the Acatlán tetra, is a small species of fish from the rivers of Mexico. It is a relatively hardy species that is able to tolerate a variety of water conditions, but is only found in freshwater, never brackish or marine. It is known only from the Río Acatlán, which is its type locality, and the Río Jía, which is a small, unknown river in the Oaxaca region.

<i>Astyanax aeneus</i> Species of fish

Astyanax aeneus, the banded tetra, is a small species of fish native to southern Central America and northern South America. It can be found in a variety of environments, including lakes, rivers, ponds, and slightly brackish locales like lagoons. As well as a varied habitat, it has a varied omnivorous diet: algae, seeds, leaves, insects, and fish fry appear to be the most common.

<i>Astyanax angustifrons</i> Species of fish

Astyanax angustifrons, sometimes referred to as the Campeche tetra, is a small freshwater fish from the rivers of Central and South America. It has a healthy distribution across southern Mexico and northern Guatemala, and is relatively common within its native range. Details regarding its diet and behavior are sparse, but it lives in areas with plentiful riparian vegetation, and most other members of the genus are omnivorous. Its habitat includes places affected by pollution and human activity; nonetheless, it is not endangered.

<i>Astyanax asuncionensis</i> Species of fish

Astyanax asuncionensis is a small species of freshwater fish described in 1972 from Asunción, the capital of Paraguay in South America. Its specific epithet is in reference to this. Currently, its range is known to encompass areas of not just Paraguay but also Argentina and Brazil. It is an adaptable, omnivorous species that easily lives in sympatry with various congeners.

<i>Astyanax bacalarensis</i> Species of fish

Astyanax bacalarensis, sometimes referred to as the Bacalar tetra, is a small species of freshwater fish found in Central and South America. Its scientific and common names both refer to its type locality, Lake Bacalar in Mexico, and it further inhabits freshwater environments like cenotes, streams, and wetlands. Its widespread nature, paired with an omnivorous diet, make it a hardy species.

<i>Astyanax baileyi</i> Species of fish

Astyanax baileyi is a small freshwater fish native to northern Guatemala. Based on several visual aspects, it was once considered a member of the genus Bramocharax, which is now obsolete, and has since been synonymized with Astyanax. As such, former members of Bramocharax are now a part of Astyanax, like Astyanax bransfordii and Astyanax caballeroi.

<i>Astyanax belizianus</i> Species of fish

Astyanax belizianus is a small freshwater fish native to various regions of Central America. Little is known of its diet or specific environmental preferences, but it was first recorded in Belize. Modern ichthyology has expanded its range into Guatemala and Honduras, where it inhabits various rivers and lake tributaries. It is a silvery fish that may have a slight yellowish tint to its scales. The body is deep, especially in comparison to similar species from the same genus.

<i>Astyanax boliviensis</i> Species of fish

Astyanax boliviensis is a small species of fish native to a handful of rivers in northern Bolivia. Its scientific name is an allusion to its range, which includes the Candelaria, Madidi, and Mamoré rivers. Though it lacks a conservation status from the IUCN, a significant portion of its habitat is contained within the Madidi National Park, one of the largest protected regions in the world.

<i>Astyanax bourgeti</i> Species of fish

Astyanax bourgeti is a small species of freshwater fish native to the upper Amazon river in Brazil. Originally described in 1908, it is not a particularly well-studied member of the genus Astyanax, but there is enough information available to establish a native range, an appearance, and potential relationships to congeners; for example, A. bourgeti is a known member of the subgenus Poecilurichthys, and has been considered such for most of its existence. Biotope preferences, sympatry, diet, and behavior are all unknown.

<i>Astyanax brachypterygium</i> Species of fish

Astyanax brachypterygium is a small species of freshwater fish endemic to a collection of high-elevation streams in Brazil. It was named in 2001 alongside congener Astyanax cremnobates, to which it bears a strong resemblance; physical details help to differentiate between the two. Its scales are a greenish-brown on the back and silver on the belly, with reddish fins and a dark humeral spot. One of its defining features is a notably short anal-fin base, which has 13 to 15 rays.

Astyanax bransfordii, sometimes called the longjaw tetra, is a small carnivorous species of fish endemic to a handful of lakes and slow-moving canals in Central America. Its range includes Lake Nicaragua and Lake Managua, which are two of the largest freshwater bodies in Central America; because it occurs only in the relevant areas of Costa Rica and Nicaragua, the area it actually inhabits is somewhat restricted. Its diet largely consists of various invertebrates and smaller fish. This is in contrast to various other species of Astyanax, which are more often omnivorous.

<i>Astyanax brevimanus</i> Species of fish

Astyanax brevimanus, sometimes referred to as the Quiché tetra, is a small species of freshwater fish native to various locales in Guatemala. Its native range is somewhat restricted, but it is a populous and adaptable species, so there is no risk of it going extinct anytime soon. It is unknown what A. brevimanus eats, or what specific habitats it prefers; current information is largely in the form of physical descriptions, general areas of occurrence, and hypotheses regarding relationships to congeners. Its silvery scales, indistinct humeral (shoulder) spot, and dark caudal-peduncle spot are features not unusual in species of Astyanax.

<i>Astyanax brevirhinus</i> Species of fish

Astyanax brevirhinus is a small species of freshwater fish known only from a river basin in northeastern Brazil. It is somewhat understudied and lacks a conservation status, but it is present in a region that is the subject of an ecological restoration project - the Jequitinhonha River. Specifics of diet and behavior are unknown, though shoaling activity has been observed in laboratory conditions.

<i>Astyanax caballeroi</i> Species of fish

Astyanax caballeroi is a small species of freshwater fish endemic to a single lake system in Mexico. It has a longer snout and more slender body than most other species in the genus Astyanax, thought to be the result of predatory behavior; while A. caballeroi eats invertebrates and smaller fish, other Astyanax species are more broadly omnivorous, and have deeper bodies with shorter snouts. This difference in body shape once placed A. caballeroi, along with several other species of Astyanax, into the former genus Bramocharax.

<i>Astyanax caucanus</i> Species of fish

Astyanax caucanus is a small species of freshwater fish only found in Colombia. While little research exists regarding its ecological habits, such as diet and mating practices, its environment preferences are known to include marshy lowlands, and it easily lives in sympatry with various other fish species in the Cauca and Magdalena river basins. It is not known to share a habitat with any other species of Astyanax, but has a noted phyletic relationship to a group of congeners including Astyanax filiferus, Astyanax stilbe, and Astyanax magdalenae.

<i>Deuterodon oyakawai</i> Species of fish

Deuterodon oyakawai is a small species of characin endemic to a large river basin along the Atlantic coast in southeast Brazil. It was originally one of three members of the genus Probolodus, but Probolodus is now considered obsolete, synonymized with Deuterodon. Much like other members of Deuterodon, and like some species in related genera, D. oyakawai is a small, silvery fish with fins in some combination of red and clear. It has a defined humeral spot that can be used for identification.

<i>Deuterodon sazimai</i> Species of fish

Deuterodon sazimai is a small freshwater fish endemic to a handful of river basins in southeastern Brazil. Upon being first described, it was considered a member of genus Probolodus; Probolodus is now considered obsolete, synonymized with Deuterodon. Much like other members of Deuterodon, and like some species in related genera like Astyanax or Jupiaba, D. oyakawai is a silvery fish with fins in some combination of red and clear. It sports a wedge-shaped humeral spot, and an oval-shaped blotch on its tail joint.

References

  1. 1 2 3 Villa-Navarro, F.; Sanchez-Duarte, P. (2016). "Astyanax atratoensis". IUCN Red List of Threatened Species . 2016: e.T49830326A61473903. doi: 10.2305/IUCN.UK.2016-1.RLTS.T49830326A61473903.en . Retrieved 29 April 2023.
  2. ↑ Bailly, Nicolas (2017). "Astyanax atratoensis Eigenmann, 1907". WoRMS. World Register of Marine Species . Retrieved 3 May 2023.
  3. ↑ Jaime, Villa (1976). "Ichthyology of the Lakes of Nicaragua: Historical Perspective". Investigations of the Ichthyofauna of Nicaraguan Lakes. 8. Retrieved 3 May 2023.
  4. ↑ Reis, Roberto E.; Kullander, Sven O.; Ferraris, jr, Carl J. (January 2003). "Genera incertae sedis in Characidae". Checklist of the Freshwater Fishes of South and Central America: 106–169.
  5. 1 2 3 4 Eigenmann, Carl H.; Ogle, Fletcher (1908). "An annotated list of characin fishes in the United States National Museum and the Museum of Indiana University, with descriptions of new species". Proceedings of the United States National Museum. 33 (1556): 1–33. doi:10.5479/si.00963801.33-1556.1. ISSN   0096-3801. OCLC   1259735 . Retrieved 3 May 2023.
  6. 1 2 Ruiz-C., R. I.; Román-Valencia, C.; Herrera-M., B. E.; Peláez, O. E.; Ermakova-A., A. (2011). "Variación morfológica de las especies de Astyanax, subgénero Zygogaster (Teleostei, Characidae)". Animal Biodiversity and Conservation. 34 (1): 47–66. doi: 10.32800/abc.2011.34.0047 . Retrieved 3 May 2023.
  7. ↑ Schmitter-Soto, Juan J. (6 May 2016). "A phylogeny of Astyanax (Characiformes: Characidae) in Central and North America". Zootaxa. 4109 (2): 101. doi:10.11646/zootaxa.4109.2.1.
  8. 1 2 "Astyanax panamensis (Günther 1864)". treatment.plazi.org. Plazi. 11 August 2021.
  9. 1 2 Froese, Rainer; Pauly, Daniel (eds.) (2023). "Astyanax atratoensis" in FishBase . May 2023 version.
  10. ↑ Scharpf, Christopher; Lazara, Kenneth J. (29 December 2022). "Order CHARACIFORMES: Family CHARACIDAE: Subfamily STETHAPRIONINAE (a-g)". The ETYFish Project. Retrieved 3 May 2023.
  11. ↑ Correa-Herrera, T.; Jiménez-Segura, L. F.; Barletta, M. (July 2016). "Fish species from a micro-tidal delta in the Caribbean Sea: species from a Colombian Caribbean Estuary". Journal of Fish Biology. 89 (1): 863–875. doi:10.1111/jfb.12860.
  12. ↑ Schmitter-Soto, Juan J. (26 June 2017). "A revision of Astyanax (Characiformes: Characidae) in Central and North America, with the description of nine new species". Journal of Natural History. 51 (23–24): 1331–1424. doi:10.1080/00222933.2017.1324050.
  13. 1 2 Sosa, Timothy (December 2012). Evolution in Fresh Waters During the Great American Interchange (PhD Dissertation). University of Chicago. doi:10.6082/uchicago.1574 . Retrieved 3 May 2023.
  14. ↑ Vilella, Fábio Silveira; Becker, Fernando Gertum; Hartz, Sandra Maria (June 2002). "Diet of Astyanax species (Teleostei, Characidae) in an Atlantic Forest River in Southern Brazil". Brazilian Archives of Biology and Technology. 45 (2): 223–232. doi: 10.1590/S1516-89132002000200015 . hdl: 10183/78925 .
  15. ↑ Souza, Rosangela Guarisso de; Lima-Junior, Sidnei Eduardo (6 May 2013). "Influence of environmental quality on the diet of Astyanax in a microbasin of central western Brazil". Acta Scientiarum Biological Sciences. 35 (2): 179–184. doi: 10.4025/actascibiolsci.v35i2.15570 .
  16. ↑ Ebus, Bram (22 May 2017). "Colombia's constitutional court grants rights to the Atrato River and orders the government to clean up its waters". news.mongabay.com. Mongabay. Retrieved 3 May 2023.
  17. ↑ Wesche, Philipp (17 November 2021). "Rights of Nature in Practice: A Case Study on the Impacts of the Colombian Atrato River Decision". Journal of Environmental Law. 33 (3): 531–555. doi: 10.1093/jel/eqab021 .
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.