Bryconops alburnoides is a small species of freshwater ray-finned fish belonging to the family Iguanodectidae. This fish is found 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.
Description Bryconops alburnoides reaches 15 cm (5.9 inches) at a maximum in standard length (tail fin not included), with a generally elongated body.Machado-Allison, Antonio & Buckup, Paulo & Chernoff, Barry & Royero, Ramiro. (1993). Las especies del genero Bryconops Kner, 1858 en Venezuela (Teleostei, Characiformes). 14. 1-20. The genus Bryconops as a whole has been described as slender-bodied and "smelt-like", similar to sister genus Piabucus;"THE FISH FAMILIES". Field Guide to the Fishes of the Amazon, Orinoco, and Guianas, edited by Peter van der Sleen and James S. Albert, Princeton: Princeton University Press, 2017, pp. 95–96. https://doi.org/10.1515/9781400888801-009 B. alburnoides is no exception. B. alburnoides is one of the larger members of the genus by a considerable margin.
The lateral line has 50 to 62 scales. B. alburnoides has a yellowish dorsal fin, which is a feature that can be used to distinguish it from other members of the genus that look similar. The upper and lower margins of the caudal fin are also tinted yellow. A congener, Bryconops gracilis, has frequently been misidentified as B. alburnoides, thanks to a yellowish dorsal fin and a similar number of lateral-line scales.Silva-Oliveira, Cárlison & Ota, Rafaela & Lima, Flávio & Rapp, Lúcia. (2021). Rediscovering species: redescription of Bryconops gracilis (Characiformes: Iguanodectidae), an often-misidentified species. Neotropical Ichthyology. 19. 10.1590/1982-0224-2021-0054. However, B. alburnoides has three rows of premaxillary teeth, while B. gracilis only has two, making for a definitive way to tell the two apart.
Taxonomy Upon describing Bryconops alburnoides in 1858, Austrian ichthyologist Rudolf Kner established Bryconops as a new genus.Kner, Rudolf. (1858). Beiträge zur Familie der Characinen. Sitzungsberichte der Kaiserlichen Akademie der Wissenschaften. Mathematisch-Naturwissenschaftliche Classe, 30, 75–80. Ανακτήθηκε από https://www.biodiversitylibrary.org/part/233420 He also described a congener, B. lucidus, but this has since been synonymized with B. alburnoides. As a result, B. alburnoides is the type species of the genus. Bryconops lucidus is the only synonym of Bryconops alburnoides.
When originally described, the genus Bryconops was placed in the family Characidae. Research from Oliveira et al. prompted Bryconops, along with sister genera Piabucus and Iguanodectes, to be moved to the family Iguanodectidae in 2011, which was revived from the work of ichthyologist Carl H. Eigenmann.Oliveira, C., Avelino, G.S., Abe, K.T., Mariguela, T.C., Benine, R.C., Orti, G., Vari, R.P., & Correa e Castro, R.M. (2011): Phylogenetic relationships within the speciose family Characidae (Teleostei: Ostariophysi: Characiformes) based on multilocus analysis and extensive ingroup sampling. BMC Evolutionary Biology, 11: 275. Therefore, B. alburnoides is a characiform fish of the family Iguanodectidae.
Bryconops has long known to be related to Brycon, Tetragonopterus, and Chalceus, which are its most closely related characiform genera. Within the genus Bryconops, B. alburnoides is isolated from the subgenus Creatochanes and from the Bryconops caudomaculatus species complex; it is not considered a member of Creatochanes, and there are six members of the subgenus Bryconops, five of which are part of the aforementioned complex. B. alburnoides is the sole remainder.
Etymology Many members of the genus Bryconops draw comparisons to other taxa, but B. alburnoides in particular bears a resemblance to members of the cyprinid genus Alburnus. This, in fact, is the origin of its specific epithet; the suffix "–oides" means "with the form of" or "resembling", hence alburnoides.
The genus name Bryconops in itself is a reference to another taxon - Brycon is a genus of characins that also lives in South America. Therefore, B. alburnoides' full scientific name means "resembling Brycon and Alburnus". The name Brycon originates in Greek, and comes from the word "bryko", which means "to bite" or "to eat".Weitzman, Stanley & Menezes, Naercio & Evers, Hans-Georg & Burns, John. (2005). Putative relationships among inseminating and externally fertilizing characids, with a description of a new genus and species of Brazilian inseminating fish bearing an anal-fin gland in males (Characiformes: Characidae). Neotropical Ichthyology. 3. 329–360. 10.1590/S1679-62252005000300002. This is in reference to the notable set of teeth that all members of the genus are equipped with.
The name alburnoides is also used for the genus Alburnoides, consisting of cyprinid fishes that inhabit Europe and Asia. Outside of similar nomenclature, Alburnoides is entirely unrelated to B. alburnoides.
Habitat and ecology Like the rest of the genus Bryconops, B. alburnoides is found solely in South American freshwater habitats.Bryconops alburnoides Kner, 1858 in GBIF Secretariat (2021). GBIF Backbone Taxonomy. Checklist dataset https://doi.org/10.15468/39omei accessed via GBIF.org on 2022-04-03. It is local to the Amazon and Orinoco river basins, as well as flood-plain lakes in the lower Orinoco region.
Bryconops alburnoides is an insectivore, demonstrating a marked preference for terrestrial insects. Its consumption increases opportunistically with windy and rainy weather, which sweeps more prey into its aquatic habitat.Silva, Cylene & Ferreira, Efrem & de Deus, Cláudia. (2008). Diet of Bryconops alburnoides and B-caudomaculatus (Osteichthyes : Characiformes) in the region affected by Balbina Hydroelectric Dam (Amazon drainage, Brazil). Neotropical Ichthyology. 6. 237–242. 10.1590/S1679-62252008000200011. This is in line with other members of the genus, all of which have a diet that consists at least partially of insects.
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