Orestias cuvieri was discovered in Lake Titicaca in deeper water layers, mainly in the south of the Lake at the peruvian side. It has synonymes as O. Pentlandi and O. humboldti.

Valenciennes named the species after the french natualist and scientist George Cuvier. (August 23, 1769 – May 13, 1832)

Nowadays Orestias cuvieri seems to be extinct as result of intrusion of rainbow trout and sea trout in 1940 in Lake Titicaca by the United States Fish and Wildlife Service. These introduction caused competitive exclusion and possible direct predation of the Orestias. Selective netting in 1960 by the Hamburg University Expedition did not bring any of them to the surface and also fisherman failed to catch any.

It was an extremely large and robust Orestias species. Had a large mouth with large teeth in a long head.

Male as female have pale gray brown coloration. Dorsally more green-yellow. The ventral part of the body is paler brown to yellow. Head is partially without scalation.

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 species is regarded as extinct it is unlikely we will ever wittness this species in life or in front of the camera.

Source:

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

Max. size 22-26 cm.
Dorsal 11-16,
Anal 14-19,
LL scale count 40-43

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).

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