Osteochilus Nashii

Datasheet

General Description

The Osteochilus Nashii, a member of the Cyprinidae family, is a rare species in the trade, often found as a contaminant among imports of other Indian species. With a maximum size of 17.8 cm, this fish is endemic to the southwesterly states of Karnataka and Kerala in India. It is characterized by its lack of a dorsal fin spine, large rostral and maxillary barbels, and darkened median fins.

Aquarium Setup

When setting up an aquarium for O. Nashii, a tank size of at least 255 liters is recommended. Mimicking a flowing river environment is crucial, with a substrate of rocks, gravel, and large boulders. Providing open swimming space and a naturalistic unidirectional flow, possibly through a giant rivertank manifold, enhances the well-being of this species. Driftwood, aquatic plants like Java fern or Anubias, and biofilm-covered rocks can be added for aesthetic and grazing purposes. Water should be spotlessly clean, with high oxygen levels and water movement.

Behaviour

Although generally peaceful, O. Nashii can cohabit with boisterous tankmates, preferably alongside cyprinids, characins, catfish, or large clown loaches. Being a shoaling species, it develops a pecking order and should be kept in groups of five or more to prevent bullying. Solitary or small shoals may lead to aggression towards similar-looking species.

Feeding and Diet

Feeding almost exclusively on small items, O. Nashii grazes on zooplankton, phytoplankton, aquatic invertebrates, and detritus, while browsing on plant leaves and rocks for aufwuchs and algae. Offering fine-grade pelleted sinking foods with added Spirulina, along with small live or frozen foods like bloodworms or Daphnia, is ideal. Feeding multiple times daily with a focus on vegetable content is preferred.

Reproduction & Dimorphism

There are no reported cases of O. Nashii breeding in aquariums. Sexually mature males exhibit pronounced tubercles and a blue hue during breeding, while females are rounder in the belly with less dramatic color changes.

Habitat and Distribution

Preferring clear, well-oxygenated, running water, O. Nashii is found in rivers and hill streams with substrates of boulders, bedrock, sand, or gravel. Endemic to India, particularly in Karnataka and Kerala, the exact distribution within these states is not extensively documented.