About the Pretty Tetra
Species Type: Freshwater Fish
Care Level: Easy. Does well in a slightly more narrow range of water parameters and shouldn't be used to cycle an aquarium. Will eat most prepared foods. May have some specific care requirements in terms of particular water parameters, social behaviors, food items etc.
Origin: South America: Upper Amazon basin in Peru, in slow moving streams under forest cover.
Compatibility/Temperament: Very peaceful and somewhat active tetra, well suited to a community tank of most characins, small catfish and loaches, rasbora, danios, angelfish, dwarf cichlids and gourami. Must be kept in a group, minimum 6 but preferably more.
This species is one of several in the Hemigrammus ocellifer group, species that have one or two humeral spots and one spot on the caudal peduncle (tail base). In this species, the caudal spot glows like copper-toned phosphorus, larger and more colourful than the closely-related and similar Head and Tail Light Tetraand there is a distinctive black wedge below the spot. There are two humeral spots, one also copper-coloured. The fish has a violet or coppery-toned sheen over the body that in certain angles under the light sparkles and glistens. The eye iris is a brilliant red.
Colourful in a well-planted dimly lit aquarium, in brighter light and spartan conditions the fish colour pales. The fish swims in the upper middle region of the aquarium, and there is a lot of interaction between members of the group. While six is the minimum, this species does better with eight or more.
The fish are ready spawners but spawning in the aquarium is not easy; it requires soft acidic water with dim light and plants in which the eggs are deposited. Males are more slender and have a pointed swim bladder which can be discerned through the somewhat transparent skin, while females have a rounded swim bladder and are thicker-bodied. When in spawning mode, the copper-red colour in the male's anal fin is much brighter than that of the female, but in my fish this is only really obvious when they are spawning.
This species is sometimes seen under the additional common names of Garnet Tetra or Black Wedge Tetra. It is somewhat rare in the hobby, but well worth searching for; a truly sparkling gem compared to the more common Head and Tail Light Tetra. A similar bodied but less colourful fish considered a possible subspecies is now established as a distinct species, Hemigrammus haraldi [Gery, 1961].
The genus Hemigrammus--the name from the Greek meaning "with half line," a reference to the incomplete lateral line--was erected as a subgenus of Poecilurichthys by T.N. Gill in 1858 but has been recognized as a distinct genus since Gery (1977). There are presently about 50 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 Hemigrammus.
None of the diagnostic characteristics presently used to describe species in Hemigrammus, including the incomplete lateral line which gave rise to the genus name, are unique to the genus. Mirande (2009) states that the genus is not monophyletic, a view shared by most ichthyologists working with the characidae. [A monophyletic genus is one wherein the species share a common ancestor, thus linking them together physiologically.] Mirande 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.
Hemigrammus has until recently been differentiated from Hyphessobrycon 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.
Gery, Jacques (1977), "Characoids of the World," TFH Books.
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).
Pretty Tetra Diet
Primarily carnivorous in nature, it will readily accept most prepared foods including flake and frozen.
Attains 2 inches.
Minimum Tank Suggestion
24-30 inches in length
Ideal water parameters for Pretty Tetra
Soft (hardness to 12 dGH) and slightly acidic (pH below 7.0) water, temperature 23-27C/73-81F.