About the Glowlight Danio
Species Type: Freshwater Fish
Care Level: Easy. Does well in a slightly more narrow range of water parameters and shouldn't be used to cycle an aquarium. Will eat most prepared foods. May have some specific care requirements in terms of particular water parameters, social behaviors, food items etc.
Origin: Believed to be endemic to the upper Ayeyarwaddy drainage in northern Myanmar. Found in small streams in the hills, having a gravel substrate with small rocks and thick terrestrial vegetation along the stream banks.
Compatibility/Temperament: Peaceful, a suitable fish for a community aquarium of non-aggressive smaller fish. Must be kept in a group, at least six but more if space allows; males are territorial and this is less of an issue with larger groups in larger tanks.
This little gem of a fish has only been seen in the hobby since 2003, although it was discovered some 70 years earlier. The orange horizontal stripe on the fish led to the common name, but this fish is not closely related to the Glowlight Tetra.
A stream aquascape having a dark gravel substrate, rocks, and side plants would provide an ideal environment for a group; the dwarf loach, other small species danio and rasbora could also be included. Floating plants would reduce the light, providing the shading this fish prefers. It spends time at the surface, and is an adept jumper and will find the smallest opening, so the tank must be securely covered.
Females are slightly larger and rounder than males, and less brightly coloured; the males' colouration will intensify when ready to spawn. This species is, like most of the cyprinids, an egg scatterer, and adults will eat the eggs if not removed immediately after spawning.
A very similar-looking fish was discovered in western Myanmar and also identified as Danio choprae by Hora in 1937. This fish was collected by Britz and Kullander in 1998 and in 2009 Kullander & Fang described it as a new species, Danio aesculapii.
Fish have been exported from the northern Myanmar range of D. choprae under the name "northern glowlight" or Danio sp. "Putao." Many considered it nothing more than a regional variant of the subject species, but it has now been granted distinct species status. Dr. Sven Kullander (2012) named it Danio flagrans, the species epithet being Latin for blazing, flaming, burning and glowing, and redescribed D. choprae at the same time.
The genus Danio now holds ten valid species reported from Myanmar.
Danio choprae was described by S.L. Hora in 1928. The species name honours Dr. B.N. Chopra, and Hora initially published the name with the feminine ending (choprae); the masculine form (choprai) is the correct gender in this case in accordance with the ICZN [International Commission on Zoological Nomenclature]. D. choprai is commonly seen, but the ICZN rules also do not allow for such corrections and the first published name must prevail.
This species was also considered in the genus Brachydanio for a time. This genus was erected by Dr. George S. Meyers (in the early 20th century) when he divided the "Danio" into three genera, Danio, Brachydanio and Daniops. During the latter two decades of the twentieth century, many ichthyologists had doubts about the validity of Brachydanio, and in 2003 Dr. Fang Fang in her study "Phylogenetic Analysis of the Asian Cyprinid Genus Danio (Teleostei, Cyprinidae)" determined that the genus Danio was paraphyletic [Greek para = near and phyle = race], which means the genus contains its most recent common ancestor but does not contain all the descendants of that ancestor. Danio was restricted to the nine species of the Danio dangila group comprised of the smaller-sized species, and the genus name Devario was suggested for the remaining larger-sized species. The former genus Brachydanio was disbanded.
In Joseph S. Nelson's "Fishes of the World" (2006), Danioninae was listed as a synonym of Rasborinae. It is generally held (though some disagree) that there are three clades within the genus Danio, and the danionin genera are within the Sub-Family Rasborinae [having priority over Danioniae] along with several genera of rasborin. The danionins can be classed as a subfamily Danioninae which is increasingly gaining credibility as a distinct subfamily from Rasborinae within the Cyprinidae family. We follow Dr. Fang's placement as the most plausible, though many speculate that the clades may end up as distinct genera.
Kullander, Sven O. (2012), "Description of Danio flagrans, and redescription of D. choprae, two closely related species
from the Ayeyarwaddy River drainage in northern Myanmar (Teleostei: Cyprinidae)," Ichthyological Exploration of Freshwaters, Volume 23, No. 3, pp. 245-262.
Glowlight Danio Diet
Insects captured at the surface are it principal food in its habitat, along with crustaceans and worms. Accepts most prepared foods, frozen bloodworms, daphnia and artemia, live insects.
One of the smallest danio at 3 cm (just over 1 inch).
Minimum Tank Suggestion
24 inches in length
Ideal water parameters for Glowlight Danio
Soft to medium hard (hardness < 10 dGH), slightly acidic to slightly basic (pH 6 to 8) water, temperature 22-26C/72-79F. Available fish will likely be commercially raised and adaptable to the given ranges; wild-caught fish require soft, acidic water.