黄鳍沙鳅 · Silver Loach

Overview

Yasuhikotakia lecontei is an elongated loach, usually brownish with golden-green reflections. It forages at dusk and after dark. Its relatively mild reputation does not remove the need for companions of its own kind or make it a solitary aquarium cleaner.

Distribution & habitat

It occurs through the middle and lower Mekong in Thailand, Laos, Cambodia, and Vietnam, as well as Thailand's Chao Phraya and Mae Klong systems. This is a bottom-dwelling fish of flowing rivers. Rocks, roots, and submerged objects provide daytime shelter before nocturnal foraging begins.

Aquarium setup

Provide a base around 120 × 45 cm or larger. Fine substrate, rounded rocks, and branching wood should create numerous hiding places. Dim light or shade from suitable plants accommodates its activity pattern. Eliminate sharp edges and trapping openings, and fit the aquarium with a secure cover.

The biological filter should be fully established. Supply ample oxygen and some flow while preventing organic waste buildup. Weekly water changes of approximately 30–50% remain necessary; powerful current is not a substitute for maintenance.

Diet & feeding

Natural prey consists principally of aquatic mollusks and other bottom-living invertebrates. Offer a varied captive diet using quality dry foods, worms, and brine shrimp, supplemented with cucumber, blanched spinach, or zucchini. Chopped earthworm should be used sparingly, and mixed gel foods are suitable additions. Neither relying on resident snails for nutrition nor expecting complete snail eradication is appropriate.

Behaviour & compatibility

Aquarium experience suggests a milder disposition than Yasuhikotakia eos or Yasuhikotakia morleti. Even so, slow and long-finned fishes remain unsuitable candidates. Active open-water cyprinids are more promising, while bottom-dwelling companions require individual assessment.

Keep at least five or six, ideally ten or more. Social rankings develop within the group. Isolated fish can withdraw or attack similar-looking species; a pair or trio risks concentrating harassment on subordinates until their feeding suffers.

Sexual dimorphism

Mature females are typically fuller-bodied and a little larger than males.

Breeding

Adults enter tributaries around the beginning of the wet season to reproduce. Young remain there initially, returning to permanent channels around November and December as flow decreases. Their dark juvenile bars fade with age. Reliable private-aquarium spawning has not been reported, and commercial techniques used for other members of the genus cannot automatically be transferred here.

Notes

Compared with Yasuhikotakia modesta, this species is slimmer. Its rounded dark marks on the sides of the tail base generally do not join underneath. Fins are commonly yellowish, but reddish-orange forms occur, so fin color alone is insufficient for identification. The identity of a so-called blue-fin form remains uncertain.

Related loaches may rest on their sides, follow each other's movements, or pale during rank disputes. Take care with erectable spines below the eyes when moving fish, since they can catch netting or injure hands.