D. margaritatus

The story of my Galaxy Rasboras

Prologue

Which fish keeper doesn't remember the year 2006. News of the discovery of a "new" fish from Myanmar spread like a wildfire and it's then purported diminutive size of only 15 mm SL coincided very nicely indeed with the beginning and already escalating hype of “Nano Aquaria”.

Enter, the “Galaxy Rasbora”.

     D. margaritatus male

First thought to be a member of the genus Microrasbora, it was, less than a year after discovery in 2006, described under the newly established genus name Celestychthis as C. margaritatus (Roberts, Tyson R. (February 2007). "The "celectial pearl danio", a new genus and species of colourful minute Cyprinid fish from Myanmar (Pisces: Cypriniformes)". The Raffles Bulletin of Zoology 55 (1): 131–140. ).

Henceforth it was known to the non-scientific fish nut as “Celestial Pearl Danio”.

Again only a few months later, the little fish was found to be a miniature Danio and accordingly belonging to the genus Danio (Conway, Kevin W.; Chen, Wei-Jen; Mayden, Richard L. 2008 Zootaxa 1686: 1–28)

Both, “Galaxy Rasbora” and “Celestial Pearl Danio” are still in use as common names, the latter clearly being the favourite since it was immediately abbreviated into yet another inevitable 3 letter acronym “CPD”.

Amongst all the taxonomic fervor and at first almost unnoticed by the greater public, things went a bit pear shape for our little critter though. Initially, D. margaritatus was thought to be “super-endemic” to a very small area near Hopong in Shan State, eastern Myanmar, east of Inle Lake, at an altitude of just over 1,000 m (3,400 ft). That tiny spot was of course depleted of fish in no time at all and the “Celestial Pearl” seemed to be extinct even before it was properly described to science. So great was the pressure, that fish keeping magazines e.g. urged their readers, only aquarists prepared to breed the species should buy them. 
The government of Myanmar banned exports of the fish in February 2007. 
Urgent warnings of the demise of D. margaritatus by Clarke, later in 2007 turned out to be unfounded though. The Celestial Pearl Danio was prolific, spawning "almost constantly", causing ponds that were thought to be empty to be restocked in only a few months time, as fry hatched, grew, and reproduced quickly. Additionally it was found, that distribution was and still is quite a bit more expansive than initially feared and the species was confirmed in waters associated with the Salween River throughout southern Shan as well as across the border into northern Thailand. Currently, the fish is captive-bred worldwide, both commercially and by hobbyists,

Me and the "Pearl"

Based on the available (mis)information, I was, at the time, hugely concerned about the survival of the habitat and of course the species itself. Not in my wildest dreams would I have participated in the termination of either or even both. So there was no way I was going to buy that little fish.

When things had calmed down and the proper state of affairs became clear, the damage was done as far as imports were concerned. But not to fear, the species had proved to be rather prolific and many a "breeder" jumped on to the celestial wagon. After all, given the price they were still fetching, it was a lucrative business indeed. A race ensued, to be amongst those, still earning a pretty penny, with partly devastating results.

Anyway, again I abstained from participating in yet another monstrosity, even if it was just by not buying these "hot bred" fishes and even if it was just a drop in the ocean.

Having said all that, it was not before the beginning of this year (2013) that I got into posession of a small group of D. margaritatus. On one of my regular visits to a wholesale dealer in my area, I noticed two tanks labled "Perlhuhnbärbling", which is the German common name for D. margaritatus, "Perlhuhn" = guinea fowl and "Bärbling" = Danio. 

The first was bustling with very small, greyish creatures, which were certainly not easily recognizable as the species in question. In the second tank, I counted 6 specimens, not any larger than their relatives next door but shimmering in  astonishing sparkles of matellic blue and glowing red. Of course the obvious difference asked for further investigation. The fellers in the full tank were, as was to be expected, tank bred specimens from a  former "eastern block" country. The six sparklers though, I was assured, were F1 of wild caught specimens (apparently from northern Thailand) bred by the dealer himself. I bagged the six, even though I'd have liked a larger group but there was no way I'd pay for those ghoulish grey slivers in the other tank.

I will spare you the details of common procedures when introducing new fish to an established tank and the short of it all is that, after an appropriate period of time, the "Pearls" were swimming all healthy and well in their destined "microhabitat", my desk tank with a length of 160 cm. And believe me, the little rascals utilize every last mm of it.
But I was still unhappy with only 6 specimens in the group. 

 

D. margaritatus two females

That was when Murphy struck again, but this time in a positive way or that's what I thought.

I got a call and was asked if I was prepared to take over the fishy contents of an aquarium, which was apparently needed for other occupants. At the mention of "Galaxy Rasbora" I hastened to signal my consent and not half an hour later I had arrived on location, well equipped with bags, rubber bands and even a small fish net. For "mental hygiene" reasons I will not go into any detail about the state of the tank. Let me just say, I was extremely sceptical that anything live should come out of it.
I didn't waste time, struck a couple of times with the net until, as far as a human eye can tell, there wasn't a living thing of more than microscopic size left in the tank. I bade a short farewell and rushed home to examine the contents of my "lucky packet"............

To be continued.