Microrasbora cf. rubescens · Flame Red 'Rasbora'

Overview

Microrasbora cf. rubescens is a small Shan State cyprinid that may represent an undescribed species. Compared with Microrasbora rubescens, it grows larger, has a green-blue lateral stripe, and carries less orange coloration. The qualification cf. remains important rather than being an optional part of the name.

Distribution & habitat

Confirmed collection context is eastern Myanmar's Shan State, where it has been taken with the celestial pearl danio, Danio margaritatus. The latter's wider Salween-associated distribution does not establish an identical range for this fish.

The shared collection setting near Hopong includes shallow, permanently wet grassland created by impounding a spring, with clear water and dense aquatic vegetation. Comparable wetlands help explain the setting, but every locality of an associated species is not automatically a confirmed site for this one.

Aquarium setup

Provide a base of at least about 60 × 30 cm and abundant plants. Gentle filtration, floating vegetation, roots, and branches create cover and soften the light.

Diet & feeding

Small invertebrates, algae, and other plankton are proposed natural foods rather than a confirmed fixed diet.

Fresh imports often arrive in poor condition and can be difficult to settle. Begin with small live foods, introducing frozen and dry products after adjustment instead of relying entirely on dry food immediately.

Behaviour & compatibility

Larger or boisterous companions may intimidate it and outcompete it for food. Similarly sized fishes using upper water appear capable of reducing shyness, although each combination needs assessment.

Maintain at least eight to ten together to reduce nervousness and allow male color and courtship competition to develop. Avoid mixing with M. rubescens, since hybridization may be possible.

Sexual dimorphism

Mature females are generally deeper-bodied and noticeably larger. Males are more compact and vividly colored.

Breeding

Reproduction of this fish may be unrecorded, so the following remains a comparison with M. rubescens. That relative scatters eggs among plants and gives no care. Separate containers with settled water and fine plants or mops can be used; dedicated lighting and filtration are optional, with an air-driven sponge filter an alternative.

Introduce a conditioned pair or small group. More adults increase egg predation, and males can distract each other. A typical event in the relative produces about thirty slightly adhesive eggs. Remove adults afterward; reference timings are 72–96 hours to hatch and another one or two days to free swimming. Begin with 5–50 μm foods, progressing to brine shrimp nauplii or microworms as mouth size permits. These figures are not verified timings for the present fish.

Notes

Asian cardinal and rose-blue-line trade labels are not formal species names. The green-blue stripe, reduced orange, and larger size help distinguish it from its relative. Genetic evidence also suggests a separate lineage, but does not justify casually replacing its qualified name.