Hyphessobrycon haraldschultzi
Crystal Red Tetra
SynonymsTop ↑
Hemigrammus haraldschultzi (Travassos, 1960)
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.
haraldschultzi: named for Brazilian ethnologist Harald Schultz (1909-1966).
Classification
Order: Characiformes Family: Characidae
Distribution
Endemic to the rio Araguaia system, the major tributary of the rio Tocantins within the lower Amazon basin in central and western Brazil, although the full range of H. haraldschultzi within the drainage is unclear.
Type locality is ‘Ilha do Bananal, Goiaz, Brazil’, referring to Bananal Island, the largest fluvial island in the world which is formed from the bisection of the Araguaia in southwestern Tocantins state.
Post-bifurcation, the eastern arm of the river is often referred to as the rio Javaés and it is probable that the type series was collected there since the Javaés runs through a portion of Goiás state.
Habitat
Little information appears to exist but presumably inhabits minor tributaries, backwaters and oxbow lakes rather than main river channels.
In the Araguaia drainage such habitats typically contain soft, weakly acidic water with the substrate covered by a layer of fallen leaves and branches.
Maximum Standard Length
20 – 25 mm.
Aquarium SizeTop ↑
Aquarium base dimensions of at least 60 ∗ 30 cm or equivalent are suggested.
Maintenance
Perhaps looks best in an arrangement comprising a sandy substrate plus some driftwood roots and branches although it will also thrive in a planted set-up.
Floating plants are a useful addition as is dried leaf litter, the latter in particular driving establishment of microbe colonies as decomposition occurs.
Such microorganisms can provide a valuable secondary food source for fry, whilst the humic substances released by the decaying leaves are also thought beneficial.
Filtration need only be gentle with an air-powered sponge-style unit normally adequate, although a degree of water movement is acceptable.
Water Conditions
Temperature: 20 – 28 °C
pH: 5.0 – 7.0
Hardness: 18 – 179 ppm
Diet
Likely to be omnivorous feeding on small invertebrates, crustacea, filamentous algae, fallen fruit and suchlike in nature.
In aquaria it may survive on a diet of dried foods but like most fishes does best when offered a varied menu which in this case should also contain live and frozen chironomid larvae (bloodworm), mosquito larvae, Daphnia, Moina, etc.
Behaviour and CompatibilityTop ↑
Very peaceful making it an ideal resident of the well-researched community aquarium.
It is perhaps best-maintained alongside similarly-sized characids, gasteropelecids, lebiasinids, smaller callichthyid or loricariid catfishes and non-predatory, small-to-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 females are noticeably rounder-bodied and usually a little larger than males.
Reproduction
An egg-scattering free spawner exhibiting no parental care.
When in good condition adults will spawn often and in a mature aquarium it is possible that small numbers of fry may start to appear without intervention, but 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 towards the upper end of 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).
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 occasionally available in the aquarium trade, although usually as bycatch among shipments of other fishes.
It is sometimes traded as H. sp. ‘Araguaia red’, H. sp. ‘Araguaia’ or ‘Schultz’s tetra’, and is included in the H. callistus species group as proposed by Géry (1977). Members of this putative assemblage are characterised by possession of a prominent dark spot on the dorsal-fin, usually with a white or yellow marking beneath. As a result, they are sometimes referred to collectively as ‘flag tetras’.
Within this artificial assemblage, H. haraldschultzi was distinguished by possession of a relatively small humeral spot and 5 or 5½/3-3½ transverse scales, and in these respects it could not be not differentiated from H. eques. The two can be separated by various aspects of colour pattern, however, most obviously that in the dorsal-fin. H. eques possesses a very large dark marking that covers most of the fin above the base, whereas in H. haraldschultzi a similarly-coloured marking is less extensive and is bordered above by a white blotch and below by a yellowish band while the base of the dark marking is parallel to the body profile.
Weitzman & Palmer (1997) expanded Géry’s concept and proposed the existence of a putatively monophyletic assemblage based on colour pattern and male fin morphology that they termed the ‘rosy tetra clade’. It was composed of species with the following shared characters which set them apart from other Hyphessobrycon species: pink to red or reddish-brown body colour; 22-29 branched anal-fin rays; 29-34 longitudinal scales; two sets of teeth on the premaxilla with 1-4 teeth in the outer series and 7-12 in the inner series.
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 colour pattern, and these definitions are still widely used today, e.g., the H. agulha group, the H. heterohabdus group, etc. These cannot be considered to represent monophyletic assemblages, however, and their concepts continue to be redefined.
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’, with one of the characters supporting its monophyly being presence of a prominent dark marking on the dorsal-fin. This assemblage, plus other morphologically similar species, is considered to represent Hyphessobrycon sensu stricto by some authors, with the remaining species included in a much-expanded H. heterohabdus group.
Others have proposed conflicting, typically more restricted, views of both the genus and/or its constituent species groups, and significant confusion remains. What is clear is that, as currently recognised, Hyphessobrycon is a polyphyletic lineage containing several genera.
The process of splitting it up has already started, and Malabarba et al. (2012) revalidated the genus Ectrepopterus Fowler, previously considered a synonym of Hyphessobrycon. They also analysed its relationships within the Characidae in the context of Mirande’s (2010) previous work, but included the type species, H. compressus, for the first time in such a study. The results demonstrated that H. compressus is more closely-related to ‘rosy tetra’ representatives such as H. eques, H. pulchripinnis, and H. socolofi than other members of the genus including H. anisitsi, H. bifasciatus, H. elachys, H. herbertaxelrodi, and H. luetkeni.
References
- Travassos, H., 1960 - Tropical Fish Hobbyist 8(6): 5-7
Hyphessobrycon haraldschultzi new species. - 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. - Géry, J., 1977 - T. F. H. Publications, Inc.: 1-672
Characoids of the world. - Hein, G., 2009 - Bulletin of Fish Biology 10(1/2): 1-10
Hyphessobrycon pando sp. n., a new rosy tetra from northern Bolivia (Teleostei, Characiformes, Characidae). - Malabarba, L. R., V. A. Bertaco, F. R. Carvalho & T. O. Litz., 2012 - Zootaxa 3204: 47-60
Revalidation of the genus Ectrepopterus Fowler (Teleostei: Characiformes), with the redescription of its type species, E. uruguayensis. - Mirande, J. M., 2010 - Neotropical Ichthyology 8(3): 385-568
Phylogeny of the family Characidae (Teleostei: Characiformes): from characters to taxonomy. - 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. - 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. - Weitzman, S. H. and L. Palmer, 1997 - Ichthyological Exploration of Freshwaters 7(3): 209-242
A new species of Hyphessobrycon (Teleostei: Characidae) from the Neblina region of Venezuela and Brazil, with comments on the putative `rosy tetra clade'. - Zarske, A., 2014 - Vertebrate Zoology 64(2): 139-167
Zur Systematik einiger Blutsalmler oder "Rosy Tetras" (Teleostei: Ostariophysi: Characidae).
