Swiss Chocolate Hognoses
Swiss Chocolate produces a western hognose with a noticeably dark head and extra dark pigment that turns it chocolate brown. Because it looks a lot like Sable but just darker, make sure to check for that dark head before you buy one as a Swiss.
About the Swiss Chocolate gene
The western hognose (Heterodon nasicus) carries a recessive melanistic gene called Swiss Chocolate. This gene adds extra dark pigment to the snake. It changes the medium brown of a normal to a deep chocolate. Breeders pair it with other genes to enrich and darken them.
Appearance
The brown of a visual Swiss Chocolate is pushed towards chocolate, making it a much darker snake than a normal. Look at the head first because most animals have a body colour that is less fixed and a head noticeably darker than the body. Some animals show yellow tones through the brown. It closely resembles Sable, but a Swiss Chocolate generally reads darker.
Genetics
The Swiss Chocolate gene is recessive. Only the visual Swiss Chocolate shows the gene, while Het Swiss Chocolate, 50% Het Swiss Chocolate, 66% Het Swiss Chocolate and Pos Het Swiss Chocolate animals all look like a normal western hognose. No super form exists. This gene has been combined by breeders with Toffee Belly, Arctic, Albino, Axanthic, Anaconda and Superconda. Swiss Chocolate with Albino is sold as Tangerine. The gene was proved out in Switzerland by Jules Toth.