Hyphessobrycon columbianus ZARSKE & GÉRY, 2002

Colombian Tetra

Etymology

Hyphessobrycon: from the Ancient Greek υπελάσσων (hyphesson), meaning ‘of lesser stature’, and used as a prefix in this case, plus the generic name Brycon.

columbianus: named for its native country of Colombia.

Classification

Order: Characiformes Family: Characidae

Distribution

Appears to be known only from the Río Acandí in Chocó Department, northern Colombia, close to the border with Panama.

Type locality translates as ‘Darien, small stream about 6 kilometers downstream from Acandi, entry of the Rio Acandi, Colombia, Atlantic coast’.

Maximum Standard Length

50 – 65 mm.

Aquarium SizeTop ↑

An aquarium with base dimensions of 90 ∗ 30 cm or equivalent should be the minimum considered.

Maintenance

Choice of décor is not especially critical though it tends to show better colouration in a well-structured, ideally planted, set-up.

Filtration does not need to be particularly strong though it does seem to appreciate a degree of water movement.

Water Conditions

Temperature: 20 – 28 °C

pH: 5.0 – 7.5

Hardness: 18 – 179 ppm

Diet

Probably a foraging omnivore feeding primarily on worms, insects and other zooplankton, as well as smaller amounts of plant material and organic detritus in nature.

In the aquarium it’s easily-fed but the best condition and colours offer regular meals of small live and frozen foods such as bloodworm, Daphnia, and Artemia alongside good quality dried flakes and granules, at least some of which should include additional plant or algal content.

Behaviour and CompatibilityTop ↑

Generally peaceful making it an ideal resident of the well-researched community aquarium.

It’s perhaps best-maintained alongside similarly-sized characids and relatives, smaller callichthyid or loricariid catfishes and non-predatory, medium-sized cichlids.

Try to buy a mixed-sex group of at least 8-10 specimens, include other schooling fishes to provide security, and you’ll be rewarded with a more natural-looking spectacle.

Sexual Dimorphism

Sexually mature males are noticeably more intensely-coloured, slimmer-bodied, a little smaller and develop a more-extended dorsal-fin than females.

Reproduction

An egg-scattering free spawner exhibiting no parental care.

When in good condition adults will spawn often and in a mature aquarium it’s possible that small numbers of fry may start to appear without intervention.

However if you want to maximise yield a more controlled approach is required.

The adult group can still be conditioned together but a smaller aquarium should also be set up and filled with mature water.

This should be very dimly lit and the base covered with some kind of mesh of a large enough grade so that the eggs can fall through but small enough so that the adults cannot reach them.

The widely available plastic ‘grass’-type matting can also be used and works well, as does a layer of glass marbles.

Alternatively filling much of the tank with a fine-leaved plant such as Taxiphyllum spp. or spawning mops can also return decent results.

The water itself should be of slightly acidic to neutral pH with a temperature within the range suggested above.

An air-powered sponge filter or air stone(s) should also be included to provide oxygenation and water movement.

When the adult fish are well-conditioned a single pair or group comprising one or two males and several females can then be introduced to each container and left in place until eggs are detected (typically the following morning).

Spawning normally occurs for 2-4 hours and a well-conditioned mature female may lay as many as 2000 eggs during this period, these normally hatching in 24-36 hours at which point the fry still have a good-sized yolk sac attached.

Initial food should be Paramecium or a proprietary dry food of sufficiently small (5-50 micron) grade, introducing Artemia nauplii, microworm, etc., once the fry are large enough to accept them.

NotesTop ↑

This species is also traded as ‘blue flame’,  ‘blue-red’, and ‘Colombian red fin’ tetra, and was misidentified as H. ecuadorensis for several years prior to its description.

Within the genus it appears to be most closely related to the Costa Rican endemic H. savagei Bussing, 1967 but differs in a number of characters as follows: possession of a significantly deeper body measuring 47.4-50.7 % SL (vs. 37.3-44.3 % SL in H. savagei); the middle teeth in the inner premaxillary row with five (to seven?) cusps (vs. 3); tooth cusps in the inner premaxillary row arranged in a straight row (vs. a semicircle); base body colour silver with iridescent blue in the upper portion in both males and females (vs. silver with iridescent blue only in the anal region of males); caudal and anal fins bright blood red, ventral fins transparent to light orange (vs. anal and ventral fins blood red, caudal-fin orange); no significant sexual dichromatism or change in colour pattern in nuptial specimens (vs. pronounced sexual dichromatism and intensification of colour pattern in nuptial specimens).

H. panamensis, native to Costa Rica, Panama and possibly Colombia, is also comparable to H. columbianus but the two can be told apart as follows: 15-17 gill rakers in H. columbianus (vs. 19-21 in H. panamensis); body depth 47.4-50.7 % SL  (vs. 35.2-39.7 % SL); dorsal-fin of male slightly longer than that of female (vs. significantly longer); base body colour silver with iridescent blue in the upper portion (vs. silvery grey with occasionally  a dark longitudinal band from the second humeral spot to the base of the caudal-fin; no significant change in colour pattern in nuptial specimens (vs. intensification of colour pattern in nuptial specimens).

Characiformes is among the most diverse orders of freshwater fishes currently including close to 2000 valid species distributed among 19 families.

This tremendous taxonomical and morphological diversity has historically impaired the ability of researchers to resolve their genetic relationships with many taxa remaining incertae sedis.

A further limiting factor has been that in many cases exhaustive study of these on an individual basis is the only way to resolve such problems.

Modern phylogenetic techniques have allowed some headway, though, and a molecular investigation of characiform relationships by Calcagnotto et al. published in 2005 revealed some interesting hypotheses.

Their results suggest that Hyphessobrycon is a member of a clade also containing the genera Astyanax, Astyanacinus, Moenkhausia, Inpaichthys, and Hemigrammus, of which all species possess five or more teeth in the inner series of the premaxilla.

A more extensive analysis by Oliveira et al. (2011) placed Hyphessobrycon in a much larger clade containing 29 genera including all those listed above.

This clade was one of three large clades, plus the genus Spintherobolus which was recovered as sister to all other characids, that formed the authors’ revised Characidae family.

Hyphessobrycon was raised by Durbin in Eigenmann (1908) as a subgenus of Hemigrammus, differing from the latter by the absence of scales on the caudal-fin.

The grouping was revised by Eigenmann (1918, 1921) while Géry (1977) created artificial groups of species based on pigmentation patterns, and these definitions are still widely used today, e.g., the H. aghula group, the H. heterohabdus group, etc.

Weitzman & Palmer (1997) hypothesised the existence of a monophyletic assemblage within the genus based on colour pattern and male fin morphology that they termed the ‘rosy tetra clade’.

They did not offer any hypotheses regarding relationships between the remaining species although Hyphessobrycon has long been recognised as a polyphyletic lineage and thus is likely to be split into several genera in the future.

De Carvalho (2011) redescribed H. compressus, type species of the genus, and conducted a molecular phylogeny incuding 227 taxa.

He concluded that Hyphessobrycon sensu stricto should be restricted to a monophyletic group of 24 species which share the unambiguous synapomorphy of the Weberian apparatus being orientated dorso-horizontally though the dorsal margin of the operculum with other defining characters comprising a black spot in the dorsal-fin and lack of visible lateral-line except in some specimens of H. pulchripinnis.

This group contains H. compressus, H. pulchripinnis, H. hasemani, H. haraldschultzi, H. troemneri, H. cf. troemneri, H. copelandi, H. takesei, H. minor, H. micropterus, H. rosaceus, H. megalopterus, H. bentosi, H. eques, H. sweglesi, H. werneri, H. epicharis, H. socolofi, H. pyrrhonotus, H. erythrostigma, H. khardinae, H. georgetta, H. roseus and H. simulans.

References

1. Zarske, A. and J. Géry, 2002 - Das Aquarium No. 391: 22-30
   Der Blaurote Kolumbien-Salmler. Hyphessobrycon columbianus n. sp. - ein neuer Salmler (Teleostei; Characiformes, Characidae) aus dem kolumbianischen Darien.
2. Calcagnotto, D., S. A. Schaefer, and R. DeSalle, 2005 - Molecular Phylogenetics and Evolution 36(1): 135-153
   Relationships among characiform fishes inferred from analysis of nuclear and mitochondrial gene sequences.
3. de Carvalho, F. R., 2011 - unpublished PHD Thesis: i-xxiii + 1-365
   Sistemática de Hyphessobrycon Durbin, 1908 (Ostariophysi: Characidae).
4. Oliveira, C. A., G. S. Avellino, K. T. Abe, T. C. Mariguela, R. C. Benine, G. Orti, R. P. Vari, and R. M. Corrêa e Castro, 2011 - BMC Evolutionary Biology 11(1): 275-300
   Phylogenetic relationships within the speciose family Characidae (Teleostei: Ostariophysi: Characiformes) based on multilocus analysis and extensive ingroup sampling.
5. Reis, R. E., S. O. Kullander and C. J. Ferraris, Jr. (eds), 2003 - EDIPUCRS, Porto Alegre: i-xi + 1-729
   Check list of the freshwater fishes of South and Central America. CLOFFSCA.