Danio erythromicron was originally described by Annendale in 1918. By then he received the name: Microrasbora erythromicron. New research has, however, discovered that this species should be placed in the genus Danio.
The name: erythromicron, stems from Latin. The first part of its name originates from the Latin word for red, erythtos. This is a reference to the red fins of the fishes. The last part: micron, is translated as small. These fish are rather small.
This Danio species has an orange color. Blue, vertical stripes can been seen on the body of the fish. This pattern covers the whole body. At the end of the tail the stripes will stop just before a blue blotch. The fins have, as mentioned before, a red coloration. This is clearest on the pelvic and anal fins.
The differences between the sexes are rather hard to see. The females are somewhat rounder bellied while the males are more colorful. However, when the fish get ready to mate, these differences become more clear. The females will become rounder, as they carry eggs by now. Furthermore, will the males show their colour at their best in order to impress others.
Distrubution and Habitat
Danio erythromicron inhabits lake Inlé in Shan state, eastern Myanmar. This species, however, can also be found in the waters surrounding lake Inlé. For instance, there have been observations of this species in the city of Loykaw.
In lake Inlé, the fish can mainly be found in the dense vegetation. In some occasions the vegetation has become so dense that it started to form “floating islands”. These islands consist of entangled plants that can support enough weight to be able to walk on it. The local population modify these islands in order to be able to grow crops on them. The Danio erythtomicron is occasionally caught between the plants that form these islands.
The lake itself consist of very clear water. The substrate is very fertile and loamy in texture. The depth of the lake is rather shallow as most parts are only 2 to 3 meters deep.
Danio erythromicron feeds in its natural habitat on small insects and their larvae. Furthermore, they tend to eat plankton and algae.
In the aquarium it can be fed with frozen and live foods. The fish can get used to dried foods. This is, however, harder with wild caught specimens. Fish that were bred in the aquarium tend to accept dried food much easier.
When feeding these fish, one needs to keep in mind that it rarely gets up to the surface. Therefore it will be necessary to feed food that sinks.
To mimic the natural habitat of the Danio erythromicron, is it necessary to fill the tank with a lot of plants. In order to make the fish more comfortable and to make the colors of the fish at their best, a black substrate would be preferred.
Danio erythromicron is rather harmless towards other species. However, it is important to take into account that these fish tend to be out competed for food by bigger and more dominant species. This Danio behaves totally different towards specimens of its own species. They can be rather aggressive towards one another. It is therefore not uncommon to see fish with nipped fins. In order to spread the aggression, a large shoal size is recommended. 20 specimens or more would be ideal for this species.
Breeding Danio erythromicron
Breeding these fish is not very hard. it is not uncommon that these fish will breed in a community tank. As these Danios tend to eat their own fry, not much of the eggs will eventually grow to mature fish. So in order to increase the yield of these fish a separate aquarium has to be set up. This breeding tank should contain a lot of plants with small leaves. One could use, for example, Taxyphillum for this. It is, however, also possible to fill the tank with wool mops. Either way there has to be enough of them in order to mimic the dense vegetation where these fish normally live. Lightning is not needed and too bright lightning might even prevent the fish from breeding.
When the tank is set up, one pair of these fish can be introduced for the tank. When adding fish to these tanks, keep in mind that the more fish the higher the change is that eggs will be eaten. When these fish are in a good condition the fish will start to spawn and scatter about 30 eggs across the aquarium.When the eggs are laid the fish should be caught.
After 72 hours the eggs will hatch. Three to four days later will the fry start to swim freely across the tank. Once the fry starts to swim can they be fed with very small food. This food has to be very small. One could use very small dry food or Paramecium. Do not feed Artemia naumplia until the fish are large enough to eat them.
Conway, K. W., Chen, W. J., & Mayden, R. L. (2008). The “Celestial Pearl danio” is a miniature Danio (ss)(Ostariophysi: Cyprinidae): evidence from morphology and molecules. Zootaxa, 1686, 1-28.
Kottelat, M., & Witte, K. E. (1999). Two new species of Microrasbora from Thailand and Myanmar, with two new generic names for small Southeast Asian cyprinid fishes (Teleostei: Cyprinidae). Journal of South Asian Natural History,4(1), 49-56.
Kullander, S. O. (2015). Taxonomy of chain Danio, an Indo-Myanmar species assemblage, with descriptions of four new species (Teleostei: Cyprinidae).Ichthyological Exploration of Freshwaters, 25(4), 357-380.