PROMOTE THE HOBBY THROUGH OPEN MINDED EXCHANGE OF KNOWLEDGE AND IDEAS - Share your experiences as a breeder or novice both good and bad. Pass on your experiences and share results with the next generation. A successful breeder will be remembered for such efforts...

Tuesday, April 12, 2011

Platinum Swordtails - When is Pink not really Pink?

Platinum Swordtails - When is Pink not really Pink?

© Alan S. Bias
Permission granted for nonprofit reproduction or duplication of photos and text with proper credit for learning purposes only.

The first time I saw a picture of a Schimmelpennig Platinum Sword I fell for the old adage "Now I have to have some of those".  Not only for obvious beauty found in this phenotype, but to decode the genetic makeup.  Trouble was it would be quite a few years before I obtained any to work with.  Sometime after 2002 I acquired a couple trios, similar to these below, from several sources including Darryl Tsutsui in Hawaii. 

Schimmelpennig Platinum Strain

Initially I did little with them other than place selection emphasis on long double swords with a visible clear area between rays to meet IFGA standards.  Caudal shape in each litter was both double sword and lyretails.  At the time I had little interest in the lyretails and selected only for doubles.  Even after 5-6 generations of selection for long even swords, spread was often narrow compared to those with more colored rays.  Phenotype appeared homozygous for grey bodies & gold platinum, with green base body color, & either white or yellow finnage.    

F1 Schimmelpennig Platinum * Vienna Lower @ 5 months
After several generations I decided to really work with platinums and devoted two dozen tanks in an attempt to understand their potential by incorporating the genetics of my Gold Vienna Lowers.  Arising out of Vienna Emerald's the cross seemed a compatible.  The resulting F1 offspring, similar to these grey body males, now additionally contained genotype for gold (blond) & grey body, gold & silver platinum, green & purple base body color, yellow & white finnage to name a few.

With little rhyme or reason in breedings I would swap off between sibling sisters or further infuse Vienna females.  To this day I still use this process.  It seems to allow for a form of dilution in the platinum.  Possibly a heterozygous expression of part it's components.  I decided to concentrate on gold (blond), but it would be several more generations before all would be expressed with regularity in a given generation.  Over the next couple of years in typical fashion for my lines I isolated Line A in pure gold and Line B as a combined grey / gold.  In the latter breeder males are normally grey, while females selected in both grey and gold.

3 month old males
In successive generations overall caudal shape deteriorated.  While the Platinum males pass genetics for double swords, this hinted at additional input from straight run females lacking in crosses with my Vienna Lower females.  Many males at maturity had very blunt swords and little clear area between rays.  Some where even on the verge of becoming veils.  This posed a dilemma since many of these same fish also expressed the more interesting combinations of phenotype I was trying to bring out.   

I have followed the results of Asian platinum breeders via the internet for a number of years.  The diversity of type they have created from Schimmelpennig Platinums Swordtails is varied.  Resulting in strains of deltas, veils, pintails, lyretials and swordtails.  Many of the sword and lyretails still suffer from poorer finnage.  I suspect from my ongoing results issues from gene complexes linking platinum and finnage will continue for some time.  Similar to those found between Stoerzbach and short sword length.

In the end I decided to select for a balance between thicker swords & bit less length, with just a break in color between the rays.  While I lost the extreme length and thinner swords I had obtained in the lines I showed, it still avoided some of the pitfalls I see in other breeders fish.

F1 Schimmelpennig Platinum * Vienna Lower @ 3 months
So when is Pink not really Pink? When the phenotype results from a combination of genotype including gold body, gold/silver platinum and purple base body color in both white/yellow finnage.  Silver platinum is by far the most visible, though gold platinum provides a similar result based on the males ability to change color depending upon mood.

Still, based on phenotype it sure looks pink to my eyes.  Just another one of those potential conflicts arising between hobbyist names & genetic description found within the hobby... 

5 month month old male

5 month month old males


Click on blog photos to enlarge

Click on blog photos to enlarge