南尼低线鱲

Overview

A faint broad flank line and variable short bars characterize Opsarius koratensis. The bars can be indistinct or absent. This unobtrusive pattern belongs to an active river fish with substantial feeding and swimming energy.

Distribution & habitat

Core records cover the middle and lower Mekong of Thailand, Laos, and Cambodia, plus the Chao Phraya, Mae Klong, and Vietnamese Dong Nai. At least one upper-system record comes from Yunnan.

It apparently uses larger, deeper, more turbid rivers than many relatives. Slow to moderate flow over stony substrates and ample oxygen are characteristic. A preference for comparatively warm conditions has been suggested.

Aquarium setup

Provide a large footprint and extensive open space. Sand, gravel, worn rocks, and wood suit a river arrangement, with hardy attached plants if desired. Maintain clean established filtration, oxygenation, and moderate circulation. Weekly water replacement of about one-third to one-half is advised. Never introduce it to an immature system, and secure all lid openings against jumps.

Diet & feeding

The main feeding pattern centers on surface insects, with small fishes and bottom invertebrates also possible prey. Offer varied frozen or live additions alongside good prepared food. Small feeder insects should receive nutritious food before being offered.

Behaviour & compatibility

Slow or timid fish may be intimidated at meals, and tiny species may be eaten. Choose robust partners of comparable size. A group of five or more distributes hierarchical pressure more effectively than two or three; solitary fish may target similar-looking species.

Sexual dimorphism

Females are usually larger, fuller-bodied, and less vivid, especially before spawning.

Notes

Morphological and molecular differences suggest that generic placement may eventually change. This remains an unresolved possibility rather than a completed renaming.