About the Buenos Aires Tetra
Species Type: Freshwater Fish
Care Level: Very Easy. Will tolerate a wide range of water parameters including pH, temperature and hardness. Can tolerate higher nitrate levels than other fish and is hardy enough to withstand the cycling process. Will readily eat prepared foods and has no special care requirements.
Origin: Rio Parana basin (Brazil, Paraguay and Argentina) and Rio Uruguay basin (Brazil). Occurs in rivers, streams, lakes and ponds. sometimes live in logs in a river bed.
Compatibility/Temperament: Somewhat peaceful if kept in a large group of 8 or more, but has been known to fin nip. Very boisterous and active, not suitable for aquaria containing slow, sedate or shy fish.
One of the hardiest aquarium fish and thus well suited to beginners but it has behaviours that must be considered; it is very boisterous, can be a fin nipper, and will usually eat plants. When kept in small groups (less than 6) it can be very nasty. It prefers the middle reaches in the aquarium. An albino strain has been developed.
Males are more colourful, particularly in the unpaired red fins, and females are rounder. A typical egg-scatter that is easily spawned; parents will eat the eggs if not removed immediately after spawning.
The species was originally described in 1907 by C.H. Eigenmann as Hemigrammus anisitsi. L.R. Malabara re-assigned it to the genus Hyphessobrycon in 1989 on the basis of the scaled caudal fin [see more below]. In 1923 and 1928, E. Ahl had described this fish as Hemigrammus caudovittatus and Hyphessobrycon erythrurus respectively, considering these were different species; Zarske & Gery in 1995 established these names as synonyms of Hyphessobrycon anisitsi (Eigenmann 1907), now the accepted name.
The genus Hyphessobrycon--the name from the Greek "hyphesson" [believed to mean "slightly smaller"] and "brycon" [=to bite]--was erected by C.H. Durbin in 1908 and presently contains more than 100 valid species. The classification is deemed incertae sedis [Latin, "of uncertain placement"]. It was formerly considered within the Subfamily Tetragonopterinae, but Javonillo et.al. (2010) suggest that this subfamily should be restricted to species within the genus Tetragonopterus since they do not share physiological characteristics with species in other genera such as Hyphessobrycon.
Authors that have recently studied the systematics of the genus Hyphessobrycon have unanimously pointed out that the group is not well defined and its monophyly is yet uncertain. [A monophyletic genus is one wherein the species share a common ancestor, thus linking them together physiologically.] Mirande (2009) for example has proposed several revisions to the Family Characidae based upon phylogenetic diagnosis. Some genera have been moved to a new Subfamily, while others are now (temporarily) assigned to a specific clade within the Family pending further study. The recognition of groups of species [clades] within Hyphessobrycon is based primarily on similarities of color patterns; an hypothesis of its intra-relationships is currently unavailable, except for the rosy tetra clade proposed as monophyletic by Weitzman & Palmer (1997).
Hyphessobrycon has until recently been differentiated from Hemigrammus solely on the basis of the fish in Hemigrammus possessing a scaled caudal fin; this however is now known to be unreliable, since it occurs in intermediate conditions (de Lucina, 2003).
de Lucena, Carlos Alberto Santos (2003), "A new characid fish, Hyphessobrycon scutulatus, from the Rio Teles Pires drainage, upper Rio Tapajos system (Ostariophysi: Characiformes: Characidae)," Neotropical Ichthyology 1 (2), pp. 93-96.
Javonillo, Robert, Luiz R. Malabarba, Stanley H. Weitzman and John R. Burns (2010), "Relationships among major lineages of characid fishes (Teleostei: Ostariophysi: Characiformes), based on molecular sequence data," Molecular Phylogenetics and Evolution, Vol. 54, No. 2 (February 2010).
Mirande, J. Marcos (2009), "Weighted parsimony phylogeny of the family Characidae (Teleostei: Characiformes)," Cladistics, Vol. 25, No. 6 (July 2009).
Weitzman, Stanley H. & Lisa Palmer (1997), "A new species of Hyphessobrycon (Teleostei: Characidae) from the Neblina region of Venezuela and Brazil, with comments on the putative 'rosy tetra clade'," Ichthyological Exploration of Freshwaters volume 7 (no. 3), pp. 209-242.
Buenos Aires Tetra Diet
Omnivorous, in its habitat it feeds on worms, insects, crustaceans and plants. It will accept almost any prepared food, frozen foods and live. It will eat some plants, aggressively some writers report.
Attains close to 3 inches (7 cm); some authors mention 3.5 inches.
Minimum Tank Suggestion
36 inches in length.
Ideal water parameters for Buenos Aires Tetra
Soft to moderately hard (hardness up to 20 dGH), slightly acidic to basic (pH 6 to 8) water, temperature 18-28C/64-82F. All fish commonly available will be commercially raised and adaptable. Wild-caught fish require soft, slightly acidic water.