New base morph: the Tolosa gene

Gene Request Form

Coming from a selection of farming specimens, this new mutation is proven co-dominant after producing offspring with an identical visual phenotype and after producing some combos.

Species: Python regius.
Name of Gene: Tolosa (just the latin name of my city in south of France!).
First produced by whom: Caperan Reptiles.
Year First Produced: 2010.
Genetics Type (Incdom/Codom/Recessive/Polygenic/etc): Co-Dominant.
In complex with other genes?: I think not! I produced some combos with the Het Red Axanthic gene and it’s not allelic! For the Hurricane gene, Blitz or Trick I don’t have obtain the same visual result on my combos.
Other names/aliases for it?: The original name of this project was “BSB” for Black Spotted Back (recurring patterns on the back).

The background color is brown with many blush on the dorsal.

The pattern is dark, the coloration varying from chocolate brown to black.

The coloration change with age but do not tarnish and contrast.

The dorsal is made of a “chaotic” pattern which can be partially or entirely “Black Back”, traversed along its length by spots of lighter ovoid shapes provided with a dark colored spot in their center.

The sides are made of ocellus-shaped patterns whose interior designs are of an aberrant type, made of small “picot” spots or more or less continuous lines.
Above these spots or lines always appears a slight border of a lighter color.

The belly is white covered on its sides with many black spots.

Of course, like all mutations, there is a more or less pronounced variability of the basic phenotype.

Proven: To what degree it is proven out to not just be polygenic? Because I produced several Tolosa and some combos.
Unique: Why do you believe this is a new morph and not an existing one? Because I breeding ball pythons for over 15 years and in a fast moving market, you have to keep up to date with the news every day! However, I have never seen an identical mutation.

Problems: Only one problem on this project, I produced on super form (dominant, defintely) male in 2017 but he was a bad feeder and he’s finally dead the same year. To fix it, I have somes females who are finally ready!


  • 2008: Acquisition of the first farming specimen.
  • 2010: First breeding Tolosa x Super Pastel.
  • 2012: Breeding Tolosa x Lesser.
  • 2013: Breeding Tolosa x Het Red Axanthic.
  • 2014: Breeding Tolosa x Tolosa: female died during pregnancy.
  • 2016: Breeding Tolosa x Mojave Enchi YellowBelly.
  • 2017: Breeding Tolosa x Tolosa Pastel: Super form (dominant gene) proven.
  • 2018: Breeding Tolosa x Clown.
  • 2019: Breeding Tolosa x Yellow Belly.
  • 2021: Breeding Tolosa het Clown X Clown Pastel.
  • 2021: Breeding Tolosa het Clown X Ivory Enchi Fire Pastel.

Disagreement or Controversy: Not to my knowledge.

References here on the community:


Tolosa Combos

Tolosa pastel adult female

Tolosa Het Red Axanthic adult male


Tolosa Enchi Fire Yellow Belly




Tolosa Lesser


Tolosa Het Red Axanthic


Tolosa Yellow Belly


Tolosa Pastel het Clown


Tolosa Enchi Yellow Belly


Tolosa Pastel Yellow Belly


Super Tolosa




Tolosa Clown Pastel


Tolosa Pastel


Reminds me of a black pastel!
I love it.

1 Like

Have you actually bred out the combo and shown that it produced a normal and/or the combo again? Simply not producing a dramatic combo is not proof that these are not allelic


This is an interesting one…

@caperanreptiles i hope you dont mind, ive added the combo images from your site to the post above?

can you possibly share pictures of full clutches?

1 Like

Now you’ve done that, I don’t see the tolosa in the pastels, yb, or clown etc.
so now I’m confused haha

Thank you for your explaination and yes my male have breeding 3 times.

It’s not a problem and yes, good idea I surch this!