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David Marshall
Title: The Russian Cobra Guppy
Summary: David has kept this strain of beautiful guppies for ten years now. He describes his various trials and tribulations along the way.
Contact for editing purposes:

Date first published: September 2004
Publication: Aquarticles, and Ryedale Reporter, Ryedale Aquarist Society, England
Reprinted from Aquarticles:
March 2005: Fish Talk, Atlanta Area Aquarium Assoc. 
Internet publication (club or non-profit web site):

   1. Credit author, original publication, and Aquarticles.
   2.  Link to  and original
        website if applicable.
   3.  Advise Aquarticles
Printed publication:
Mail two printed copies to:

David Marshall,
16 Potter Hill,
North Yorkshire
YO18 8AA
And one copy to:
4342 Capilano Road,
North Vancouver.
British Columbia. V7R-4J7

The Russian Cobra Guppy

By David Marshall
Editor of the Ryedale Reporter, Ryedale Aquarist Society, England

When I decided to put together a talk for the members of the Ryedale Aquarist Society on my experiences with the Russian Cobra Guppy (cultivated form of Poecilia reticulatus), so many notes were made that I decided to use these notes to write a small article for the Aquarticles web-site.

In the autumn of 1994 I visited an aquatic retail outlet in West Yorkshire. The outlet manager and I had three things in common - we both had a passion for unusual aquarium fish, adored guppies and were avid soccer fans. This gave us plenty to talk about. On this particular visit the manager became very excited as soon as I walked through the door and pointed a finger towards one of the guppy holding tanks.

In solitary confinement was the most beautiful male guppy that I have ever seen. Of the typical cobra shape he had a dazzling bright green body complimented with a blood orange tail that was highlighted with several black bars. A label on his tank read 'Russian Cobra Guppy - true strain'. If you look at the Russian Cobras on page 31 of the T.F.H. book 'Guppies - Fancy Strains and How to Produce Them' by Noboru Iwasaki you will get a good idea of the fish we are talking about although the colour pattern of the fish featured here is a little different.

The manager told me that he had been given the chance, by his wholesaler, to purchase 12 male and 12 unmated females of this particular strain. On arrival he had separated the two sexes into different aquaria. Once the males settled he had the shock of seeing them engage in what he described as 'all out war' as they nipped at each others bodies and fins so badly that he was forced to separate them. A week on and only the one male, who had dished out aggression but avoided harm, remained alive. Not having the time to work on this particular strain himself the manager had 'put him aside' for me.

I could not resist this 'free gift' and was given the opportunity to purchase the 5 remaining females at cost price. These females were very reminiscent of the Singapore xanthic varieties except that they had much brighter light blue-orange colours in their tails (caudal fins). Looking back I now realise that the Russian breeders had colour fed both male and females. The manager told me that the wholesaler had informed him to keep these particular fish in an aquarium that contained bogwood as not only did this show off their colours to full effect but also they were the most acidic water loving guppies he had ever come across.

Once home the 6 fish were placed into a 24x12x12" aquarium containing mature bogwood etc. I was of the opinion that the presence of the females would calm the aggressive nature of the male. My opinion would soon turn out to be misguided as within a few hours he had dispatched one female to the 'big aquarium in the sky' and had the other 4 cowering at the surface of the water.

The 4 remaining females were left in this aquarium while the male was moved to one of 18x18x18". A few days later the females were added, on a single basis, and left in his company for varying amounts of time. His mating vigour was almost frightening to watch and never have I witnessed either a male guppy or male of any fellow livebearing species (including Limia) show such aggressive virility. I have to admit that the females were quite 'shell shocked' afterwards but without taking this risk we would not have had a future generation to work with.

30 days on and 3 (who would eventually produce 6 broods each) of the 4 females were showing the dark 'gravid' signs around their anal area. During the night they gave birth to a total of 18 fry, saved due to packing the tank with aquarium plants, and these were removed to a separate aquarium. Four weeks on and I found the first young guppy dead on the gravel. The next dead guppy was found a couple of days later. Having the time to watch made me realise that a dominant male had 'come to the fore' and that he was already killing his rivals. So as soon as the first signs of a gonopodium appeared the young males had to be moved to new quarters and yogurt cartons certainly proved handy tools.

In their mating behaviour the young males had all the traits, and the body colour, of their father so it was a laborious, but worthwhile, task in order to let them go through the reproductive process. At least the females were able to share a community aquarium.

Over the next 3 generations the situation did not change and it took so much time and space to keep the strain up and running. Various crossings of generations did not help. Then, with the 5th generation, I noticed a change in the behaviour of the young males and from this time onwards they began to, slowly, act as 'normal' guppies do with each subsequent generation becoming less and less aggressive. This was a great relief but had an initial drawback as the vibrancy of male body colours began to slip away. Around the same time variations in the body colours of the females was also becoming very evident.

Then an even greater drawback occurred. With guppy strains you always have the risk of 'fall back to wild type' and, without realising it, the fastest developing males were suddenly no longer Russian Cobra but green-yellow top swords (at least we know some of their ancestry). These have plagued some generations but have, thankfully, been kept under control and now they find themselves kept with females that I do not wish to breed from or are given away to fellow hobbyists. In all honesty these are lovely fish, although not as long lived as the Cobras, in their own right but I have never had the space to try and establish their strain.

Despite almost losing the strain on more than one occasion, living with the fact that the number of fry produced is much smaller than with a number of other guppy strains and finding that the females of some generations are just not worth breeding from I have now maintained, and crossbred, my Russian Cobra strain for ten years and to do this made them the only strain of guppy in my care (although I have just purchased a male and two female German Yellow). Of the various guppy strains I have kept this is the only one never to have produced a single fry with a bent back etc.

There have been two big disappointments with these fish. Firstly the loss of colour in the males, but this is countered by the fact that I was able to maintain less aggressive offspring of both sexes in the one tank and in community set-ups alongside Corydoras and small characins etc. Secondly although I have given many small groups of youngsters to 'good homes' over the years (and seen some mature males appear on the show benches as a result) very few have become established and gone beyond a second generation.

Before we finish it must be mentioned that I have found these fish easy to care for and, like all guppies, they are constantly looking for food and to reproduce their kind. The wholesaler was right as Russian Cobras dislike hard water conditions and dull their colours as a result. These fish have provided me with so much pleasure over the past decade.