There are some really strong evidences that Transparent scale is not able to shorten swords extensions in guppies. Despite this there are still opinions that Transparent scale is capable of downsizing delta to roundtail. To verify that hipothesis let’s take a look on what broadtail guppy really is.
Ds/Ls + Cp = Broadtail
Ds/Ls – double sword/lower sword
Cp – Pigmentierte Caudalis
Broadtail – szeroki ogonek
Examples of beautiful swords (lower and doubles) are on internet. But what is this pigmentierte caudalis gene?
It is as straightforward as it seems. Cp is just colored tail fin. However as above pictures shows coloration is not enough to have a nice broadtail. Nature needs additional information to create a beautiful, flowing fin in male guppy. Luckly we breeders have an easy way to communicate to nature that we want colored fins extended to the form of broadtail. And this information, that we can use in communication with nature are sword alike extensions.
Of course as time flows new ways of communicating to nature that we want nice shaped tail fin have surfaced up.
Following above inference (broadtail = swords + pigmentierte caudalis) leaves us with simple conclusion. Transparent scale seems to have no bigger influence on tail fin shape than other autosomal melanophores modificators (like blond) or to bemore precise any other autosomal genes. In other words – deltas with transparent scale are no problem!
Transparent scale sometimes manifest itself in phenotype as absence of shining factors in guanine levels – it is actually lack of melanophores that change relation of reflected light to absorbed one. However useful that’s not the only way to recognise Ts in phenotype. Transparent scale (as blond) is melanophores modificator. Therefore it’s features are strongly linked with melanine expression within phenotype. In fish with transparent scale melanophores seems to prefer upper part of the fish body. They also form some kind of cluster below dorsal fin. Let’s take a look on some pictures to have our imagination working.
Let’s sum up a little bit. In swords lines there was no corelation between swords length and transparent scale presence observed. Because modern broadtails are built on solid basis of swords there are no good reasons to assume that transparent scale can downsize broadtail to roundtail. Therefore, at least for now, I would rather say that there is simply a roundtail gene. From delta breeder’s perspective there is no reason to beware more of Transparent scale than any other autosomal genes (long term concentration of autosomal genes may be the reason for deteriorative effects on fins and body size/shape).
Demonstration of few Transparent scale alleles in future would not be a great surprise by analogy of another melanophores modificator – blond.
In one of future posts we will discuss little bit other genes that actually could affect broadtail shape. As example we will use some mosaic phenotypes which sometimes in middle of tailn fin have indentation. Which more often than not is yellowish…