Click for Larger ImageFor the past several years, both authors have extensively worked on metallics in their breeding programs. Their experiences and thoughts on the metallic trait were written down in several articles (“Copper gold” (2003)[1]; “Metallics and Masks” (2005) [2]; “Understanding metallic genetics” (2006) [3]). Both authors decided to team up in order to share their thoughts and experiences on “dragons”.

It is clear that the development of the metallic betta was the catalyst of a true “bling-bling”-fever among betta hobbyists worldwide. Metallics have greatly influenced the betta hobby and opened doors for many breeders to develop new color varieties and combinations.Following the metallic betta which made such a prominent mark on the betta hobby, a new variant came hard on its heels. The unique appearance of this so-called “dragon” betta is characterized by a thick, solid silvery/white metallic layer which almost resembles armor.”Dragons” captured the imaginations of betta breeders the world over,leading to the hype that has been humorously termed “dragon fever”. But what exactly are “dragons”, where did they come from and are they really different from our metallics?

According to Pichet (Interfish breeder team – Thailand), the first”dragons” were created by using a “super” red plakat, a red copperplakat and Betta sp. mahachai [8]. With some difficulty, the wild Bettasp. mahachai was crossed to the red copper plakat with the intent ofpreserving the Betta sp. mahachai traits in the offspring. Then a youngmale from this spawn was crossed to a super red plakat female. Thethird step was a mother x son backcross: the super red female wascrossed to one of her offspring in a method commonly referred to as’line breeding’. Although the body shape and finnage of the fry was notvery good and some of them even showed malformations in the body, thecolor was there and the first dragon pair was born! The first “dragons”were developed by Mr. Tea. The “Red dragon V1″ were first presented tothe Thai public in the December 2004 edition of a magazine called”Fancy Fish” by the Interfish breeder team [9].

“Dragons” – Genetics?
We know that the first metallic bettas were created around the year2000. It took about 5 years before Dr. Leo Buss provided publishedseveral papers which provided us with more information and insightabout the genetic make-up of this phenotype [15-18]. By now the sametime-span has passed since the first “dragons” were developed but sofar not much is known about genetic make-up and inheritance of thisphenotype and thereby leaving us with quite some unanswered questions:

What genes determine the “dragon” phenotype?
We can clearly see that the unique appearance of the “dragon” clearlyaffects the iridescent layer. So far several genes have beencharacterized which affect the iridescent layer, for example theclassical iridescent colors steel blue (blbl), turquoise (BlBl) androyal blue (Blbl), metallic or yellow reflecting iridophore (thewildtype variant of the reduced yellow iridophore locus) [18] and thespread iridescence gene (Si) which is responsible for the increase indensity and distribution of the iridescent color. 
In 2007, Joep van Esch of made some experimentalcrosses with “dragons” in his fishroom in order to learn more about theheredity behaviour of this trait (see pedigree below). After crossing a”dragon” to a regular metallic he observed that all offspring had a copper phenotype. Considering thefact that a copper phenotype (homozygous metallic steel blue, blbl ++)can only be obtained when the offspring obtains one steel blue (bl) andone metallic (+) allele from each parent [3], this result suggests thatboth traits may play an important role in the unique appearance of the”dragon” phenotype. Interestingly, the metallic scaling of theoffspring seemed more thick and solid than observed in regular metallicfish. This characteristic was also passed on to the offspring when aheterozygous “dragon” was crossed to a heterozygous metallic fish. The offspring resulting from crossing two heterozygous metallic sibblings resulted in homozygous, heterozygous and non-metallic offspring withoutthis unique appearance which was observed before. Off course we have tokeep in mind that these findings were purely based on macroscopicobservations (with the naked eye). Nevertheless, these crosses showthat the “dragon” trait is hereditable and suggests that it behavesquite dominant as it already clearly affects the iridescent layer inheterozygous fish.


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