Tessera Corn Snakes
Instead of standard saddles, a Tessera corn snake has a thin stripe on the back and small blocks in a mosaic pattern on each side. Because a snake with two copies looks exactly like one with a single copy, a super label requires breeding records to back it up.
About the Tessera gene
Tessera replaces the saddles of a corn snake with a thin stripe along the spine and a busy mosaic of small blocks on each side. It was the first corn snake pattern gene shown to be dominant, so it shows in the first generation from a single Tessera parent. It has been bred into many colour morphs.
Appearance
A Tessera has a narrow stripe of the lighter ground colour instead of the saddles. This stripe, which is usually tan, pale orange or creamy yellow, runs down the back and has an edge of black, dark brown or grey. While some animals have one clean stripe from neck to tail tip, others have a stripe broken into dashes. Most sit between these two, with a nearly complete stripe that has a few notches and gaps. The morph gets its name from the sides. These show a tessellated pattern of ground colour and darker saddle colour where the pieces are usually outlined in black, dark grey or brown. These patterns range from tidy to fairly busy. The eyes usually have a black pupil and match the body. The head can show any normal corn snake head pattern in the body's colours. The belly varies more than anything else, from plain white with no checkers to almost solid black. Many are lightly checkered at the neck and more heavily further down. The tail follows the body. A Super Tessera looks the same as a single-copy animal, and nothing tells the two apart by eye.
Genetics
Tessera is a dominant gene. Because the pattern shows if an animal has one copy or two, there is no het. A corn without the pattern does not carry it. Some listings use terms like co-dom or incomplete dominant, but dominant is the right word since there is no visibly different super. The gene is listed as Tessera and Super Tessera. You should ask the seller what breeding records back a Super Tessera label because the super cannot be picked out by eye. It is not allelic with Motley or Stripe and sits in no complex, even though the striped back invites comparison with both. On the market, there are combinations like Amel Tessera and Okeetee Tessera. Don Soderberg of South Mountain Reptiles proved the gene dominant in breeding trials in 2008.