Fishes / Habitat

Lambchop Rasbora: A Softer Take on the Harlequin

The lambchop rasbora, Trigonostigma espei, is a close relative of the harlequin rasbora and easily confused with it, though its black body patch is smaller, more triangular and does not extend as far

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In this guide

Overview

The lambchop rasbora, Trigonostigma espei, is a close relative of the harlequin rasbora and easily confused with it, though its black body patch is smaller, more triangular and does not extend as far forward, giving the fish a slimmer, lighter appearance overall. It comes from Thailand and Cambodia and grows to a slightly smaller three to four centimetres.

Its more compact size and slightly deeper orange-red body tone make it a popular choice for smaller planted tanks and nano aquascapes where the standard harlequin might look a touch large. It is worth knowing that three closely related Trigonostigma species, the harlequin, the lambchop and the less common glowlight rasbora, are frequently mixed up and sold under overlapping names such as false harlequin rasbora, so the exact species on the label is not always reliable.

Tank and water requirements

A group of eight or more suits a tank of thirty five to forty litres upwards, slightly smaller than what a full-sized harlequin group would need given the lambchop's smaller adult size. It shares the harlequin's preference for soft, slightly acidic water but adapts reasonably well to typical Indian tap water conditions.

A densely planted tank with quiet water flow shows this fish at its best, and it tends to appreciate a bit more cover than some of the bolder tetras.

Diet and behaviour

Small flakes, micro pellets and occasional live or frozen food suit its small mouth well. It is peaceful and shoals confidently once settled, though it can be shy in an understocked or overly bare tank.

It pairs well with other small, calm nano fish such as ember tetras or chili rasboras rather than larger, boisterous tankmates.

Buying tips

  • Priced around thirty to seventy rupees per fish, generally a touch more than the standard harlequin rasbora given its smaller supply in India
  • Often sold alongside or mislabelled as harlequin rasbora, so check the smaller, narrower black patch to confirm the species
  • A good fit for a nano planted tank rather than a large, open community setup

Article content © Ravi Teja. All rights reserved.

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