Common Name: False Rummynose Tetra
Origin and Habitat: Upper Amazon basin, Rio Perus (Peru and Brazil), Rio ***** and Rio Madeira systems (Brazil). Found in clear water habitats (small rivers and streams with low flow, bays and lagoons), frequently sympatric with the Neon Tetra in Peru.
Compatibility/Temperament: Very peaceful, must be kept in a group of at least 6 but preferably more is space permits; well suited to a community aquarium of similar peaceful characins, dwarf cichlids, rasbora, smaller barbs and danio, small catfish. This species rather than the smaller Brilliant Rummy Nose Tetra will manage with angelfish.
False Rummy Nose Tetra Diet
In its habit it feeds on small aquatic invertebrates and algae. In the aquarium, generally a surface feeder although they will often eat from sinking foods; will accept most dried foods that are small (ensure some of these have a high vegetable content), frozen bloodworms, rotifers, daphnia. Live wingless fruitflies and daphnia would be a good treat.
Size
Attains 2.8 inches, the largest of the three Rummy Nose species.
Minimum Tank Suggestion
24 inches in length.
Water parameters for False Rummy Nose Tetra
Soft to medium hard (< 12 dGH), acidic (pH below 7) water, temperature 22-26C/72-79F. This species, unlike Hemigrammus bleheri, occurs in clear waters with a pH between 6 and 7 but the hardness and pH should not exceed the upper end of the given ranges.
Description
There are three distinct species, Hemigrammus rhodostomus, H. bleheri, and Petitella georgiae under the common name "Rummy Nose Tetra." The subject species is the largest of the three and easily distinguished from the other two, chiefly by having the largest caudal fin (tail) with the widest white bands of the three. The red colour is the palest and does not extend beyond the head. Also, the central caudal fin band clearly extends laterally onto the body of the fish (though it is much lighter than on the fin) and is broader in this species. The chart included below illustrates the three species. When this species and H. bleheri are included together in the aquarium, they will mix and form a single shoal as they swim through the aquarium, remaining in the lower third of the water column.
This fish will only exhibit its brightest colouration in a well-planted aquarium with a dark substrate and slightly acidic and soft water; floating plants would be ideal, as this fish like its cousins does not appreciate bright lighting. This species is sensitive to water parameters and conditions, even moreso than most characins.
Females are rounder than males; this species is reported as difficult to spawn, and this will only be successful in very soft and acidic water. The species is an egg scatterer, and the adults will readily eat the eggs if not removed; like the other rummy nose species the eggs and fry are sensitive to light.
This species was the second of the three "Rummy Nose" tetras to be discovered; the species was described and named by Jacques Gery and H. Boutiere in 1964. Recognizing that this fish was physiologically distinct from Hemigrammus rhodostomus, Gery & Boutiere erected the genus Petitella [the name derived from the French petit meaning small, diminutive] for this species, which is still the sole species in the genus.
The genus Petitella was previously considered within the subfamily Tetragonopterinae, but this classification has for some time been deemed incertae sedis [Latin for "of uncertain placement"]. In a study published in 2010 (Javonillo et.al.), it was determined that the subfamily Tetragonopterinae should only be used for species within the genus Tetragonopterus. Also, Mirande (2009) proposed several revisions to the family Characidae based upon phylogenetic diagnosis. Some genera have been moved to a new subfamily, while others such as Petitella are now (temporarily) assigned to a specific clade within the family pending further study.