The type locality of Orestias elegans is a small lake at the headwaters of the Rimac River in Peru. According to Garman the " Lagunas de la Corderilla de la Ascencion, orígin del Rio de Santa Eulalia que se reune con el Rio Rimac que pasa por Lima". (Where both rivers merge).

Villwock (1986) has doubts about the distribution of an Orestias species in the Rimac River and suggested that the types originated from the Apurímac River in the Urubamba basin.

The species belongs to the Orestias agassizii species group.

Synonyme: Orestias agassii elegans; Tschernavin 1944.

A rather slender Orestias with reduced squamation. The scales on the anterior part of the body are distingly larger than those on the posterior part.

The life colors are not known. The specimen in musea do not show colors anymore and show only a weak spotted pattern.

Members of this genus have been generally maintained and bred only under controlled laboratory conditions rather than as aquarium fishes. Therefore, information about maintainance and breeding is present here as part of the general information about the genus rather than under each individual species. This information is based mainly on that obtained in the laboratory of the zoological Institute and zoological Museum, Hamburg (Villwock, 1995b)

Keeping and breeding Orestias species in captivity requires that the water is relative cool with temperatures between 10 and 15 C. Optimal water temperatures would be about 13 C.

Today it is believed that the species from the genus Orestias reach sexual maturity when they still display juvenile coloration and morphology. At that stage it is very difficult to recognise the sexes.

Eggs are deposited one by one or in a small cluster in fine substrate like live plants with fine leaves. Development of the eggs takes about 4 weeks due to the low temperatures the eggs should be stored. Youngs grow slow and can be fed by artemia nauplii and small worms and crustaceans

Remarks :

Because this special treatment the genus Orestias is seldom found in the tanks of hobbyists.

Source:

R. Wildekamp, "A world of Killies" , Volume 4.

Max. size 8,5 cm.
Dorsal 15,
Anal 16,
LL scale count (average) 34-38

Morales, P., Gajardo, F., Valdivieso, C. et al. Genomes of the Orestias pupfish from the Andean Altiplano shed light on their evolutionary history and phylogenetic relationships within Cyprinodontiformes. BMC Genomics 25, 614 (2024).

https://rdcu.be/dOnkA