Galaxy rasbora, Microrasbora sp. Galaxy

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Matt Clarke explains how to keep and breed the newly discovered Galaxy or Fireworks rasbora, Microrasbora sp Galaxy - a species now under threat.

Common name: Galaxy rasbora, Fireworks rasbora, Rasbora toei, Celestial pearl danio, Chilli rasbora

Scientific name: Microrasbora sp. "Galaxy". Currently being described and due to be placed in a new genus shortly.

Origin: Myanmar. The supplier wanted to keep the exact collection locality under wraps for commercial reasons. It was eventually discovered to be a micro-habitat wetland area east of Inle Lake.

Habitat: According to the exporter, his species lives among dense vegetation in a cool, high-altitude wetland region in a marsh area fed by a spring. It lives in sympatry with Danio sondhii and the undescribed Rosy loach, Yunnanilus sp.

Diet: Early reports suggested that the fish might only consume tiny live foods, so most people have been feeding theirs with live Daphnia, brineshrimp or microworms. However, most have reported that these will also accept small dried foods such including Tetra Mini Granules and crumbled flakes, as well as live Tubifex.

Size: A miniature species that is believed to be fully grown at around 1.5cm in length. However, there are some reports of the fish reaching up to 3cm.

Water: Lives in moderately alkaline water with a temperature of around 24C or less. Collectors have claimed that the water in the collection locality is at pH 7.3 with a hardness of 7 GH (235 microsiemens). They seem very adaptable. Some of the Singapore fishkeepers who were first to obtain the species reported success in keeping them in small blackwater tanks with a pH ranging from 4.5-5.7. In the UK, they've happily acclimatised to our harder, more alkaline water without problems.

Aquarium: Due to its tiny size, this beautiful little cyprinid would be best in a small aquarium, away from larger fish that might look upon it as a tasty snack. You could keep an impressive little shoal of these in a tiny desktop aquarium such as the AquaCube we gave away with last month's Practical Fishkeeping subscription. No details on the habitat are available, however, aquarium observations seem to suggest that the fish likes well-aerated or flowing water. Most fishkeepers are keeping theirs in small planted aquariums, in which the species is the only inhabitant.

Notes: New fish don't come much newer than this: the species was only discovered a few weeks ago (August 2006) and was first introduced by Kamphol Udomritthiruj of Thailand-based exporter AquariCORP. The first specimens arrived in the UK during September. Practical Fishkeeping was the world's first magazine to break news of the species.

Conservation status: Sadly, we reported in February 2007 that a supplier had visited the type locality and discovered that other collectors had gone to the area and fished it so heavily that catches were down to just a few dozen specimens per day. The conservation status of the species now looks bleak and we would advise all fishkeepers to avoid this fish unless they have the skills to breed the species in captivity.

Identification: Undoubtedly a new species but only tentatively considered a Microrasbora due to its resemblance with Microrasbora erythromicron. Unlikely to be confused with anything else, given its striking appearance. It is due to be placed in a new genus, along with M. erythromicron, later in February 2007.

Sexing: Quite simple to sex when the fish are in good condition. Males are brighter coloured and have bright red fins with squiggles of blue-black in the dorsal and anal, and the upper lobes of the caudal fin. The chests of males are also more orangey and they tend to be slimmer. Females are slightly less colourful, with less red and fewer dark squiggles and uncoloured pelvic fins. They have rounder bodies and a slightly paler overall colour. Both sexes have the same chunky appearance seen in Danio choprai and the hump-backed of Microrasbora erythromicron.

Breeding: Pete Liptrot and Paul Dixon of the Bolton Museum Aquarium were the world's first fishkeepers to spawn this species, and they managed to do just a couple of weeks after the fish first became available in the UK. Very little is known about reproduction. Paul says that he observed a brightly-coloured male attempting to drive females into a spawning mop and Pete found seven small eggs in a clump of Java moss a week later and spotted some fry which had already hatched. Said Pete: "The eggs have been laid over Java Moss and appear to be only very slightly adhesive, they drop out of the moss very easily. We've removed the moss to another aquarium to see what else hatches. As we were moving the moss one of the smaller males was very busy hunting around for eggs or fry."

Behaviour: Males can be rather quarrelsome with each other and often flare, spar and fight resulting in minor splits to the fins. Most people keeping these in groups of six plus have observed shoaling in their fish, and several have reported minor territoriality in males.

Availability: This species was first imported into Singapore in mid-September and arrived in the UK a week later. Both Wildwoods and BAS currently have hundreds in stock and the fish has also appeared on import lists used by other suppliers around the country, so the fish should be more widely available soon. One supplier was referring to the fish as the Fireworks rasbora and cited the name Rasbora toei, which is fictitious. As I predicted in early September 2006, a few weeks after this fish was discovered, I think this species has massive commercial potential for the small aquarium market. It has undoubtedly been the most talked about fish species of 2006, and the century so far.

Price: Prices vary, but currently around 6 each. We highly advise fishkeepers to avoid this species, unless they are capable of breeding it.

This article was first published in the December 2006 issue of Practical Fishkeeping. The stunning photograph is the work of Aaron Koo.